What usually starts out with harmony, trust, lotsa love and incredible sex, has a good chance of turning sour and latest when you start thinking about splitting ways, even relationships become business deals. Attorneys get paid, division of assets, allocation of funds, associated debt will be assigned, etc. So, when you compare the last line to the first line - it's Love vs. Business. In the end, no one on this planet would consider a partnership in a business without contractual/prenup backup. Which is pretty much your answer.
Trust me, not having one was a VERY costly mistake for me...i'd definitely advise to get one drawn up.
Is there a way to present it nicely? Yeah, because each and every benefit or profit is a nice thing, thus, when it comes straight down to it, it's for her and your protection, benefit and safety. Unless she can assure you that it will NEVER come to a split, which no rational person can do, she's probably going to see your point.
*lecture end*
