It seems like they often end up with older men. For example Aladdin has been various listed as being either 18 or 21. Many of these films end with the princess either engaged or married or at least in a "true love happy ever after" relationship.
Am I imagining this or do a lot of Disney princesses end up this way?
Snow White: Yes. As you stated, she's 14 (15 by the end of the story) and according to production notes, Prince Florian is intended to be 18.
Cinderella: Unknown. She's 19, older than most Disney Princesses, but I can't find an age for Prince Charming.
Aurora: Yes. She's 16, and while I can't find an age for Prince Philip either, he met Aurora shortly after her birth and was already a young boy by then, so he's a few years older than her.
Ariel: Yes. She's 16, and according to the film's novelisation, Prince Eric is 18.
Belle: No.She's 20 at youngest, and possibly older. The Beast is 20 for most of the film and turns 21 right at the end, when the last petal falls (it's fated to do so on his 21st birthday). So it's possible Belle is actually older than him.
Jasmine: Yes. She's 15, and Aladdin is 18 - although he was initially planned to be as young as thirteen before they aged him up.
Pocahontas: No. While she does fall in love with John Smith, he travels back to England at the end of the film and they do not pursue a romantic relationship.
Mulan: Most likely. Mulan is 16. I can't find an age for Shang but, given that he's already a captain in the army, he is probably older than that.
Tiana: Unknown. She is apparently 19 (there's a sequel book about Naveen trying to find a 20th birthday present for her), but I can't find an age for Prince Naveen.
Rapunzel: Yes. She's 18, and Flynn Rider is 26, the largest age gap between a Disney Princess and her love interest.
Merida: No. She doesn't fall in love with anyone.
Moana: No. She doesn't fall in love with anyone.
Elsa and Anna aren't officially Disney Princesses, but for completion's sake: