Unpopular opinion: Stella leaving Ted at the altar was mostly Ted’s fault
If you try and watch Shelter Island from Stella’s point of view, I think you could interpret Stella leaving Ted as understandable.
The main thing is obviously Ted inviting Robin. Not only was it bad to do in the first place, but the way he did it was awful. He lied to Stella about not inviting her when she asked him not to, and then also made some comment about him and Robin having sex a year back mid-argument. Bearing in mind this is Stella’s wedding day, she’s about to commit to a bloke who is saying this about his ex girlfriend, of only about a year. We all saw how crazy Lily got in the build up to her wedding.
Not saying Ted is entirely to blame, Stella could have handled it better and not rushed it etc., but Ted definitely did more bad than Stella in my opinion.
Furthermore, I remember my first watch, I hated Stella after the wedding bride, but from Tony’s point of view, a lot of the stuff did happen. Not to mention him telling Tony that he stuck it to her when he was picking up Lucy. So I don’t think it’s that bad, at the end of the day it’s a Hollywood film and they would have had to exaggerate it that way anyhow.