I concur with the "if you're going to stop, keep your gear" contingent. i gave up the guitar for five years because i "didn't feel like i had anything to say someone didn't say better years ago." eventually the desire to play returned; apparently part of my ennui with music was a side effect of medication for depression, and when i changed medications the desire came back in less than two weeks.
perhaps i'm assuming too much, but from your post it sounds like you've got other stuff going on that is affecting your frustration level as well. don't transfer frustration from one stimulus to another.
one other thought: if we were all able to play like angels, or like super-duper professionals, we'd be doing it. but there's equal value in just hitting a simple chord, sitting back, and listening to it ring...as long as YOU get something from it. happy isn't defined by perfection, and whether that happiness is for you alone, for you and someone else, or for you and a whole room of someone elses, it's equally valuable. it's just that in the case of an audience that happiness is shared. would i like to be able to make records like the ones i admire? well, duh. but until it no longer makes me happy to wind up the amp and do a long bluesy bend on the G string, i'm on it. if i can do something that other people also appreciate, i'll be overjoyed. but--not to sound selfish--i'm doing this, on whatever level i'm doing it, because it makes ME happy. if that isn't enough, maybe you're expecting too much for/of yourself. the inability to play basketball like Michael Jordan doesn't mean you can't have fun shooting a few hoops.
Thanks again,
Karl
