Naw. Here's my completely uninformed theory:

Melania is Trump's second wife, and he's exactly the kind of douchebag who'd have an iron-clad pre-nup. I think she's staying with him because (a) he probably doesn't touch her anymore, and spends his little-hands time with other women, (b) he's still a source of income for her, and (c) she gets nothing, or a pittance, if she divorces him. It may be that if he divorces her, she gets a payout, which would explain why he hasn't moved on to wife #3, but he's got the cake and is eating it, too; the real conundrum is why she hasn't left him yet. My money's on a pre-nup.