I need serious help about making a relationship decision?

I think you & your girl need to have a sit down together and talk this out. You both need to ask each other where your relationship stands at the moment. Breaking up and getting back together makes an unstable & unhealthy relationship. You both need to know that you're willingly committed before you get married. Ask her if she's mature & ready to make such a commitment. If she does break up with you again, don't take her back. She needs to know that you will not tolerate this kind of behaviour. Good luck.