Sex and relationship

I'm currently approaching the end of my years in college and my boyfriend is 2 years older than me. I KNOW this guy is the ONE. I've never felt like this with anyone before and he's more than amazing to me. Obviously we've talked about marriage and our plans and what we would do when I graduate...meaning moving in with each other/ living arrangements. However I come from an EXTREME catholic family that doesn't believe in cohabitation before marriage. My dad has mentioned many times before that it's wrong and that "I better not do that" when in my gutt I WANT to. How do I deal with this issue with my parents?