This looks really cool. Like other people have said, I'd take a look at TaskWarrior and some of their functionality.
Having it inside a git repo is really, really awesome.
Hey man, we all go through rough patches in our life. You're at a very good position right now to do something about it. You have a lot ahead of you. Looking at the past, and making unrealistic goals for the future won't help. Look at the present, what can you do right now to make things better?
It's not going to happen in a day, it'll take time. We're all strong and you can get through it.
Talking to someone helps. We've all been there and when I talked to a professional it made the world of a difference, but see what you can do for yourself first.