Prenuptial/Antenuptial agreements do not provide a bullet-proof protection for the wealthier person's assets, despite what a lot of people think. If you made the money before getting married, and you don't co-mingle those assets (basically mix them up, same checking account, home purchase, etc), most courts allow a concept of tracing that can often be more valuable in protecting "what you came in with" then a prenuptial agreement signed before the big money was made. The shorter the marriage is, the easier this is.
If the big money is made after you've been married, the presumption is that the poorer spouse "contributed" to that (even if they watched TV all day while the other spouse worked 90 hour weeks) so that kind of agreement tends to be harder to enforce than one that covers money earned before marriage.
Even in situations where both parties had their own legal counsel, a bullet-proof prenup was drafted and every contingency planned for, a divorce court judge can still basically "override" parts of to make a "equitable division of property" i.e. "I don't think this is fair, so we're gonna split it differently than the prenup says" (You
don't want to be on the wrong side of one of those decisions)
Add to this mess the fact that every state has different rules (e.g. community property states in particular) and some consider sliding scales based on length of marriage, relative contribution, each partners expected future income, whether one party pisses off the divorce judge, etc; the bottom line is nobody truly knows how a prenup is going to work until that fateful day arrives.
My two cents, talk about money BEFORE you get married, better to not have the first time 2 people find out they have differing ideas about who gets what be when they are glaring across the table at each other with a couple $300/hour attorneys next to them. Its amazing the # of people getting divorced I see come into our office that have literally lived together for years, and have polar opposite ideas of who brought what into a relationship. The ones that fight the most seem to literally know
less about each other's expectations of whose money is whose than probably most WF posters know about their pizza delivery guy's finances.