I'd say melania clearly doesn't like the massive press attention, yes she was a model, but this is very different indeed. She's clearly very nervous in the huge media spotlight she's now under as well as public speaking and many many people would feel the same.
I'm not in agreement that should have prevented him from going for president, simply that if he gets it to then limit her role, which is exactly what's he's doing. After this his daughter is stepping in. Fair enough.
I suspect it's more a marriage of convenience now, but I don't know them and I don't know what goes on behind closed doors. She may agree with his views, she may agree with some and disagree with others. Like any marriage. She may love him, they have been together nearly twenty years, and like his previous wives she could have left.
I feel sorry for her only to the extent she's in a very unique situation with the media that only a hand full of people really ever go through and it clearly makes her nervous.