There isn't an alternative, is there?
I know what you mean - and I'm not trying to be a pain in the ass. But there are some thoughts that will only make everything much more difficult, and I think this is one of them.
No-one here is going to condone suicide. I'm not sure that's even what you are inferring. I think the hardest part of it all, sometimes, is figuring out how to come to an understanding with yourself about the diagnosis: accepting PTSD as a thing that's happening right now, and yes it's horrible, seems unsurvivable - but it can and does change.
Personally, I've been dealing with depression for longer, and I ask myself all the time it seems, lately, 'when do I stop fighting this?'. But the answer has more to do with 'how can I stop fighting with the fact of this', instead of 'when is it going to be OK to give up?' It's never going to be OK to give up.
That's probably not what you want to hear, but I think it's the only way to survive it.
It's also very helpful for me to not engage with the future, because all I see is a very long road of days and days of suffering. If I can do one day at a time, that will be good enough for right now. That's actually more than good enough, it's gold-star-awesome, as far as I'm concerned. Other people can benefit from and handle thinking about the future....but I might suggest, right now, that you try and keep it all very small, very in the moment, and not allow yourself to wonder too hard about the details of what you might be doing five days from now, a year from now, whatever.
Try and notice the times when it's not a fight. I promise you, they are there. They may be super-small, and very fleeting, but they are there.