what to do if my gf is hiding things from me but i am afraid to loose her,brain says i should break up,heart says no. what should i do?

Asking for a few answers is always an option because you need to make sure that there is trust between you or it isn't a very healthy relationship, if she seems to be hiding things from you then you can ask her for answers, but never try to push someone into that kinda stress, ask her when timing is available, and when you feel it is good timing... talk to her and ask her about it.

Relationships are work. That might be the understatement of the century! If there is secrecy or doubt in a relationship, the best advice I have is to communicate. Ask direct questions, give direct answers, open up, share, put it all on the table. The healthiest relationships are those with strong lines of communication. Once the couple is honestly communicating, it should no longer be a battle between the brain and the heart— rather it is a sense of trust reinforced and made stronger over time. However, if lies are exposed, things are hidden, or communication is not effective; that is when you MUST listen to the brain and work through the heartache. Nobody deserves to be mistreated or taken for granted in a relationship and fear of loss is not reason enough to put up with dysfunction. Get out and find someone better.