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There are things that happen in the life of every person that upsets them, causes despair and makes their life miserable. In such a situation there are different reactions, despite the difficulties, some try hard and strive to start a new life with relying on Allah, while others only surrender to the hardships and problems they have confronted and as a result choose solitude or even worse, commit suicide to bring an end to their pain and anguish. From Islam's perspective death is not an end to our lives, but rather a start that will have no ending point in the hereafter. Therefore committing suicide will do no benefit to one who is suffering from pain. Moreover no problem in the world is worth committing suicide for and exchanging one’s life for.
From Islam's point of view the true owner of everything and everyone including us human beings is Allah and he is the one who has the right to decide about our lives. Allah has not allowed us to kill ourselves and commit suicide, consequently committing suicide will not differ from killing and murdering others, because in both cases we are taking away the life of a person and Allah, the owner of human beings, has forbidden such. The Almighty forbids people from this in the Quran, saying: "Whoever slays a soul, unless it is for manslaughter or for mischief in the land, it is as though he slew all men" 
The life of one person is not equal to the life of a society, but is similar to it, therefore in cases other than the ones Allah allowed, it is a great sin. There is no difference whether the life we are taking is ours or someone else's.
This has been mentioned in the ahadith, Imam Baqir (as) says: "A mu’min may suffer from any disaster and die in any way, but he will never commit suicide." 
In this regard Imam Sadiq (as) says: "Whoever commits suicide will stay in hell forever."  These ahadith and others show the type of approach Islam has toward suicide. Therefore, never look at suicide as a solution to any problem, even if others do not realize that one has committed suicide and he makes it look like an accident, because nothing can be hidden from Allah. Keep in mind that if you stay on the right path for some time you will be able to attract the attention of your family and relatives, and this way your family will be proud of you.
A few points that will help start a new life:
1- Try to strengthen and solidify your faith through different means.
2- Stay around joyful, optimistic and hopeful people
3- Keep away all negative thoughts and try to be positive.
4- Consult the experts in this field.
You can also refer to Questions 3525 (website: 3755) and Question 5354 (website: 5575) for more information.