We grieve after any sort of loss, but most powerfully after the death of someone we love. It is not just one feeling, but a whole succession of feelings, which take a while to get through and which cannot be hurried.

We most often grieve for someone that we have known for some time. However, it is clear that people who have had stillbirths or miscarriages, or who have lost very young babies, grieve in the same way and need the same sort of care and consideration.

In the few hours or days following the death of a close relative or friend, most people feel simply stunned, as though they cannot believe it has actually happened. They may feel like this even if the death has been expected.

This sense of emotional numbness can be a help in getting through all the important practical arrangements that have to be made, such as getting in touch with relatives and organising the funeral. However, this feeling of unreality may become a problem if it goes on too long. Seeing the body of the dead person may, for some, be an important way of beginning to overcome this.

Similarly, for many people, the funeral or memorial service is an occasion when the reality of what has happened really starts to sink in. It may be distressing to see the body or attend the funeral, but these are ways of saying goodbye to those we love. At the time, these things may seem too painful to go through and so are not done. However, this can lead to a sense of deep regret in future years.

Soon though, this numbness disappears and may be replaced by a dreadful sense of agitation, of pining or yearning for the dead person. There is a feeling of wanting somehow to find them, even though this is clearly impossible. This makes it difficult to relax or concentrate and it may be difficult to sleep properly. Dreams can be very upsetting.

Some people feel that they 'see' their loved one everywhere they go - in the street, the park, around the house, anywhere they had spent time together. People often feel very angry at this time - towards doctors and nurses who did not prevent the death, towards friends and relatives who did not do enough, or even towards the person who has, by dying, left them.

Another common feeling is guilt. People find themselves going over in their minds all the things they would have liked to have said or done. They may even consider what they could have done differently that might have prevented the death. Of course, death is usually beyond anyone's control and a bereaved person may need to be reminded of this. Some people may feel guilty if they feel relieved that their loved one has died after a painful or distressing illness. This feeling of relief is natural, understandable and very common.

This state of agitation is usually strongest about two weeks after the death, but is soon followed by times of quiet sadness or depression, withdrawal and silence. These sudden changes of emotion can be confusing to friends or relatives, but are part of the normal process of grief.

Although the agitation lessens, the periods of depression become more frequent and reach their peak between four and six weeks later. Spasms of grief can occur at any time, sparked off by people, places or things that bring back memories of the dead person.

Other people may find it difficult to understand or be embarrassed when the bereaved person suddenly bursts into tears for no obvious reason. At this stage it may be tempting to keep away from other people who do not fully understand or share the grief. However, avoiding others can store up trouble for the future, and it is usually best to start to return to one's normal activities after a couple of weeks or so.

During this time, it may appear to others as though the bereaved person is spending a lot of time just sitting, doing nothing. In fact, they are usually thinking about the person they have lost, going over again and again both the good times and the bad times they had together. This is a quiet, but essential part of coming to terms with the death.

As time passes, the fierce pain of early bereavement begins to fade. The depression lessens and it is possible to think about other things and even to look again to the future. However, the sense of having lost a part of oneself never goes away entirely. For bereaved partners there are constant reminders of their new singleness, in seeing other couples together and from the deluge of media images of happy families. After some time it is possible to feel whole again, even though a part is missing. Even so, years later you may sometimes find yourself talking as though he or she were still here with you.

These various stages of mourning often overlap and show themselves in different ways in different people. Most recover from a major bereavement within one or two years. The final phase of grieving is a letting-go of the person who has died and the start of a new sort of life. The depression clears completely, sleep improves and energy returns to normal. Sexual feelings may have vanished for some time, but now return - this is quite normal and nothing to be ashamed of.

Having said all this, there is no 'standard' way of grieving. We are all individuals and have our own particular ways of grieving.

In addition, people from different cultures deal with death in their own distinctive ways. Over the centuries, people in different parts of the world have worked out their own ceremonies for coping with death.

In some communities death is seen as just one step in the continuous cycle of life and death rather than as a 'full stop'. The rituals and ceremonies of mourning may be very public and demonstrative, or private and quiet. In some cultures the period of mourning is fixed, in others not. The feelings experienced by bereaved people in different cultures may be similar, but their ways of expressing them are very different.

Children and adolescents
Even though children may not understand the meaning of death until they are three or four years old, they feel the loss of close relatives in much the same way as adults. It is clear that, even from infancy, children grieve and feel great distress.

However, they have a different experience of time from that of adults, and may go through the stages of mourning quite rapidly. In their early school years, children may feel responsible for the death of a close relative and so may need to be reassured. Young people may not speak of their grief for fear of adding extra burdens to the grown-ups around them. The grief of children and adolescents, and their need for mourning, should not be overlooked when a member of the family has died. They should usually, for instance, be included in the funeral arrangements.

How can friends and relatives help
You can help by spending time with the person who has been bereaved. More than words comfort, they need to know that you will be with them during this time of pain and distress. A sympathetic arm around the shoulders will express care and support when words are not enough.

It is important that, if they want to, bereaved people can cry with somebody and talk about their feelings of pain and distress without being told to pull themselves together. In time, they will come to terms with it, but first they need to talk and to cry.

Others may find it hard to understand why the bereaved person has to keep talking about the same things again and again, but this is part of the process of resolving grief and should be encouraged. If you don't know what to say, or don't even know whether to talk about it or not, be honest and say so. This gives the bereaved person a chance to tell you what he or she wants. People often avoid mentioning the name of the person who has died for fear that it will be upsetting. However, to the bereaved person it may seem as though others have forgotten their loss, adding a sense of isolation to their painful feelings of grief.

Remember that festive occasions and anniversaries (not only of the death, but also birthdays and weddings) are particularly painful times. Friends and relatives can make a special effort to be around.

Practical help with cleaning, shopping or looking after children can ease the burden of being alone. Elderly bereaved partners may need help with the chores that the deceased partner used to handle - coping with bills, cooking, housework, getting the car serviced and so on.

It is important to allow people enough time to grieve. Some can seem to get over the loss quickly, but others take longer. So don't expect too much too soon from a bereaved relative or friend - they need the time to grieve properly, and this will help to avoid problems in the future.

Grief that is unresolved
There are people who seem hardly to grieve at all. They do not cry at the funeral, avoid any mention of their loss and return to their normal life remarkably quickly. This is their normal way of dealing with loss and no harm results, but others may suffer from strange physical symptoms or repeated spells of depression over the following years. Some may not have the opportunity to grieve properly. The heavy demands of looking after a family or business may mean that there just isn't the time.

Sometimes the problem is that the loss is not seen as a 'proper' bereavement. This happens often, but by no means always, to those who have had a miscarriage or stillbirth, or even an abortion. Again, frequent periods of depression may follow.

Some may start to grieve, but get stuck. The early sense of shock and disbelief just goes on and on. Years may pass and still the sufferer finds it hard to believe that the person they loved is dead. Others may carry on being unable to think of anything else, often making the room of the dead person into a kind of shrine to their memory.

Occasionally, the depression that occurs with every bereavement may deepen to the extent that food and drink are refused and thoughts of suicide arise.

CLICK HERE for a downloadable booklet and info for widows from the BBC