Seree, please don't leave...
I'm guessing life isn't being fair to you right now but that doesn't mean you just downright give up on something, especially if its art. Whether you believe it or not, you have come a long way with your drawing and you have a lot of realism in your pictures nowadays too so thats plain proof that your skills keep getting better and better.
Seriously, its not worthwhile for you to give that all up, especially since you seem to be the only one that thinks you can't draw anymore.
Just don't leave ok? I can tell you from experience as a person who has left and come back many times that art will always stick with you in some form or another and that at the end of the day its not a permanent or wise choice to try and completely abandon it.