Should i break up with my girlfriend? please help...?

Me and my girlfriend have been going out for almost 4 months, im 17 (senior) and shes 16 (junior). I am in love with her. I chased her for like 7 or 8 months until she would finally go out with me and now that we are together we have been very happy for these 4 months. the problem is, i feel like im not important at all in her life. i know she likes me, shes nice to me, we make out a lot, etc. but i wish she would just let go and fall for me. i wish she would actually WANT to be with me and act caring towards me. i can barely imagine being without her, and theres so much im still looking forward to in our relationship, but its getting rediculous. should i break up with her? if not, do you have any advice to help our relationship?