So... I'm planning to commit suicide by jumping off a bridge...
I was thinking about seeing the comments on this post before that...
I never had friends... Ever... All because of my sexuality... My grandparents fighting continuously doesn't help at all...
You may have problems and you might consider your sexuality among them. But suicide doesn't really fix anything.
There is no afterlife, in which you feel relieved and freed from your pain and if you're religions and believe in an afterlife, then most religions treat suicide as a sin which might condemn you to hell. In both regards your attempt at your life doesn't improve your situation.
Calling a suicide-hotline does. There you get to speak with people, who professionally deal with people, who have no positive outlook on life anymore and they might provide you with serious options on how to improve your condition.
You should owe it to yourself to at least try this option before doing anything drastic. What do you have to lose at this point, when you are willing to end your life? Wouldn't it at least be worth a shot to try something else first, just to get another opinion on your situation?
I get it, relatives constantly fighting is horrible, been there, experienced it. But you'll survive this. At least try to call a hotline for your immediate concerns. And if your sexuality troubles you, you can talk about it in this forum to come to terms with it or at least to understand it better. Those are the first options coming to my mind, that are better than jumping from buildings and/or structures. And I am certain there are even more options that might present themself to you eventually.