jenn, sounds like you nailed it-STRESS. it can make me irritable, angry, explosive, etc. it sounds like stress and the family issues are causing this. as for your family..you aren't being validated. and of course being thrown up against the wall is never acceptable/abuse. i'm glad you are getting away from that environment. a healthy emotional distance from them will help, imho.
you are younger than you think...lots of good life ahead of you. plus educated. jobs are very very hard to find right now, so it's not your failure in landing something. just keep chipping away at interviewing. the more you do the sharper you'll be for that job you really want.
i hope things improve for you. hope you'll keep us posted if things do or don't improve now that you're on your own. hugs, jenn