“I’ve been dating this girl off & on for 5 months. Everyone thinks she’s crazy (exce asdfadsf ”

I've been dating this girl off & on for 5 months. Everyone thinks she's crazy (except her) & will only want me when I'm gone. We have great times together where I want to marry her - & I think she feels it back - but then she'll totally go cold & pull away for a few days. I broke up w/ her but I still can't stop the addiction of her & wanting to be w/ her again. What do I do?...