SUBREDDIT: r/relationship_advice
TITLE: [17/f] My parents (50/f) & (52/m) have always had an unhealthy marriage, and I'm afraid of ending up in a situation like theirs or having my fear stop me from taking chances.
POST: There has always been cheating, constant arguing over petty things, physical and verbal abuse, gambling, talking down to one another etc. in my parents' marriage. They've considered divorce a couple of times, but my mom decided that financially and for my sister's and my sake it would be best to stay together. 

Growing up around them,  along with being a little more quiet and not-so-great with people, has convinced me that I wouldn't be able to have a healthy relationship either. I can't think of any couple I know personally whose relationship is something I'd wish for for myself. 

On top of that,  I haven't really been seriously physically and emotionally interested in anyone yet besides one of my best friends (17/m), but that could get a little messy, couldn't it? Since he's getting an arranged marriage in a few years anyway, and he's bisexual (I would rather help him feel comfortable than get comfortable and feel him up, eh?), I figured I should just drop the notion altogether, but if you have some advice on that, too, it'd be much appreciated.
TL;DR: 
I feel doomed to a relationship just as shitty as my parents'. How can I learn from their mistakes? What can I do to get over my fears?