Replying to I could use some advice from a fellow christian

hey everyone so i'm kinda in a bit of struggle right now and would really appreciate some advice. so basically i met this girl about two months or so ago and im takin her to prom and we have a thing going on. im really like her and she is a really a cool girl. she is very pretty, smart, funny, and not into herself at all. only problem is that she is agnostic and she has looser morals than i do. i don't know what to do. lately i've been partying more and all the stuff that goes along with that. i haven't been praying or going to church as much and my relationship with God seems to be faltering. i don't know what to do. I feel like maybe God wants me to use our relationship to bring her to Christ but i feel like if thats the case i'm not doing His will. i don't what to do. if anyone could give advice or share a similar personal experience i would be very grateful!