The idea of humanity and life on Earth I feel is a gift and when someone chooses to kill themselves they are not only disrespecting themselves, they are valuing their death as more important than living. No matter how hard things get, Kant would say just deal with it and respect humanity as an end in itself.
All Enlightenment thinkers who wrote on the subject – Hume, Voltaire and Rousseau among others – agreed that the religious condemnation of suicide was not only preposterous but also entirely lacking in charity. Kant, on the other hand, denounced suicide in the most unqualified and indeed quite furious terms. According to him “suicide is in no circumstances permissible.” The man who commits suicide “sinks lower than the beasts.” We “shrink from him in horror.
Suicide is usually a permanent solution to a temporary problem. However, death should be every person's right. Sometimes through suffering and/or pain, whether physical or emotional life becomes not worth living to an individual. I believe that the individual has a right to terminate his/her life if that decision is reached on a calm and rational level. Suicide is not immoral; sometimes prolonging suffering is indeed immoral.
http://plato.stanford.edu/entries/suicide/