So totse I've been seeing this girl for almost 2 years now, at first it was a typical relationship, 6 months into it, I broke up with her as I was going through a low point in my life and did not want to drag her into it. After the break up we remained fuck buddies for about 9 months, we've slowly moved back into an open relationship.

Fast forward to now. She told me she has not kissed/slept with or even dated any other guys since 2 years ago, while I on the otherhand have slept around etc, she told me she loves me and can't go on without me and wants us to have a proper relationship again (Proper meaning closed) and start thinking about a future together.

She gave me a few days to think about it and call her back (this just happened about an hour ago over the phone).

Quick details
Her:1st year Med student age 21
Me: 3rd year math/econ student age 19

I thought because of the age gap she wouldn't want to have a proper relationship with me.

what to do?!!?!