I don't know how much I agree with all this but if it helps anyone...
It is important to interpret the stages loosely, and expect much individual variation.
There is no neat progression from one stage to the next.
In reality, there is much looping back, or stages can hit at the same time, or occur out of order.
So why bother with stage models at all?
Because they are a good general guide of what to expect.
For example, generally, a long period of "depression" (not clinical depression), isolation, and loneliness happen late in the grief process, months after the tragedy strikes.
It actually is normal and expected for you to be very depressed and sad eight months later.
Outsiders do not understand this, and feel that it should be time for you to "get over it" and rejoin the land of the living.
Just knowing that your desire to be alone with your sad reflections at this time is normal will help you deal with outside pressures.
You are acting normally. They just don't "get it".
Here is the grief model called "The 7 Stages of Grief":
1. Shock, Disbelief and Denial:
You will probably react to learning of the loss with numbed disbelief. You may deny the reality of the loss at some level, in order to avoid the pain. Shock provides emotional protection from being overwhelmed all at once. This may last for weeks.
2. Pain and Guilt:
As the shock wears off, it is replaced with the suffering of unbelievable pain. Although excruciating and almost unbearable, it is important that you experience the pain fully, and not hide it, avoid it or escape from it with alcohol or drugs. You may have guilty feelings or remorse over things you did or didn't do with your loved one. Life feels chaotic and scary during this phase.
3. Anger and Bargaining:
Frustration gives way to anger, and you may lash out and lay unwarranted blame for the death on someone else. Please try to control this, as permanent damage to your relationships may result. This is a time for the release of bottled up emotion. You may rail against fate, questioning "Why me?" You may also try to bargain in vain with the powers that be for a way out of your despair ("I will never drink again if you just bring him back")
4. Depression, Reflection, Loneliness.
Just when your friends may think you should be getting on with your life, a long period of sad reflection will likely overtake you. This is a normal stage of grief, so do not be "talked out of it" by well-meaning outsiders. Encouragement from others is not helpful to you during this stage of grieving. During this time, you finally realize the true magnitude of your loss, and it depresses you. You may isolate yourself on purpose, reflect on things you did with your lost one, and focus on memories of the past. You may sense feelings of emptiness or despair. 7 Stages of Grief...
5. The upward turn:
As you start to adjust to life without your dear one, your life becomes a little calmer and more organized. Your physical symptoms lessen, and your "depression" begins to lift slightly.
6. Reconstruction and working through:
As you become more functional, your mind starts working again, and you will find yourself seeking realistic solutions to problems posed by life without your loved one. You will start to work on practical and financial problems and reconstructing yourself and your life without him or her.
7. Acceptance and Hope:
During this, the last of the seven stages in this grief model, you learn to accept and deal with the reality of your situation. Acceptance does not necessarily mean instant happiness. Given the pain and turmoil you have experienced, you can never return to the carefree, untroubled YOU that existed before this tragedy. But you will find a way forward.
You will start to look forward and actually plan things for the future. Eventually, you will be able to think about your lost loved one without pain; sadness, yes, but the wrenching pain will be gone. You will once again anticipate some good times to come, and yes, even find joy again in the experience of living.