I think the jeans pocket on her dress is more insulting to OP and his normally impeccable style than her playing tonsil hockey with Ioan in front of him.
I thought the exact same haha!
(not a response to the quote now, just general thoughts): Honestly, I don't think OP was that bothered about losing Alice, he was probably relieved that someone else would take her and the problem would go away.
They stayed in touch and friendly so I don't think he was particularly upset, just my take.
I don't really like the whole painting of Ioan as being this dumb babe in the woods who was spellbound by the brazen hussy Alice, he was an adult making his decisions back then just as he is now, he was with Alice because he wanted to be and it worked for him. He married her because when he weighed up losing her or marrying her, he chose to marry her (clearly it wasn't something he was thrilled about, but he still chose to do it, nobody had a gun to his head). I don't think we need to infantilise a grown man because we can't fathom the idea of choosing to be with someone like Alice.
Loads of people love the drama and excitement of being with someone like her, they get off on the ups and downs and unpredictability, the cycle of busting up and making up, she was attractive physically back then and worldly and confident, it's not hard to see why someone would want to date and be with her and it's a bit strange IMO to be feeling now, with hindsight, mad at or uncomfortable with Ioan for having been with her. He was with her for two entire decades. Clearly on some level it worked for him. Until it no longer did.