I will agree with what Shuttles said above.
But I add this. Personally I think if I could change things I would have never got married. You can be together, have kids together, girl can legally change her last name to yours without marriage (at least in my state). And in case things don't work out, you are not legally obligated to split and/or pay alimony (but child support should their be kids involved).
You can still have a big wedding like party and do all the dressing up, but then never legally obligate yourself to splitting everything. Or if you do get married pray you don't accumulate wealth during, as a prenup only protects what you bring into the marriage at the beginning and not anything accrued during the marriage.