Help!

So I'm not a virgin, yet my parents think I am still. If I tell my parents, they will freak. We're the Christian "wait for marriage" family so my parents would not be happy.....the problem is, that my boyfriend and I have talked about getting on the Pill or another birth control but I dont know how to do it without my parents finding out since I'm on their insurance. My boyfriend is in the army right now and we haven't done anything for three months but when he comes home we plan on making love again. So any advice?