Letting the wild horse run free

I've been coming to terms that my girlfriend is the kind that likes to do things by her own rules even if they aren't the best decisions in life. I don't know if its because I've given up, I'm indifferent or I am really just accepting her for who she really is, warts and all.
I hope that eventually things would work out and also even if she does mess up she would owe it to me to tell the truth. I hate all this suspicions and the lack of trust.
However a tiny bit of me thinks that isn't it selfish to be allowed to just run off like that and do your own thing and I'm suppose to just wait around for her to come back? Where is the compromise?