I have both been in (still am somewhat) your situation but also experienced what the aftermath of losing someone you loved in such a way makes you feel.
I guarantee you one of their first thoughts and feelings will be similar to the ones you are going through right now. The aftermath is messy, painful and absolutely fundamentally life changing.
Is it fair to ask someone to live through suffering for others only? I would say no but at the same time I also personally feel that we have a responsibility to our loved ones, those who care about us more than we do ourselves.
There is no right answer in this and I don't want to pretend like I sit on any high horse morally, I tried to take my life once but I misjudged my method and fucked up. Afterwards I started having a "fuck it I'll try" mentality that has given me a lot of opportunities over the years.
Today I can say I enjoy many parts of my life, my thoughts still exist, the pain of my loss haunts me everyday but I have learned how to co-exist with it to the best of my ability and because I managed that I've gotten the pleasure of experiencing happiness and daring to hold a dream for my future.
The fact that you're holding on for others shows your compassion and that the person you are in its core is good, please never forget that.
I hope you all find peace from your suffering.