I'm thinking we should just cut out vacation short

Me and my husband are on a vacation we have been saving for about a year now. We are in Florida visiting friends and my family. My husband has also really wanted to go to Disney World since he's never been and he has a lot of inner child to get out. We went yesterday and wanted to go a few more times until we leave next week but he got a text message from one of his cousins . She had a conversation with my husband's "mom" and said she really wanted him to stay calm but just thought he should know. He read it and I didn't know what was going on at first. We were at dinner with my parents and I saw his eyes change and I asked was he okay and he said yes. My mom noticed and she asked and he said that he's fine. Then started crying and went out to the car. He got in the car and I held him and let him cry and he told me what his "mom" had said to his cousin. I put Mom in air quotes because she's technically his aunt. His biological mom was on severe drugs as a teenager when she got pregnant with him and she took him in and adopted him.

All day he hasn't wanted to go back to Disney or go out at all. He's just wanted to stay in our hotel and I've been laying with him. I've been thinking about just cutting the trip short because he's not having fun anymore. I'm not having fun anymore. Even my parents aren't because they are so concerned for him. I talked about cutting the trip short but my mom thinks that's letting his "mom" ruin the trip for him. But I can't see how we can save it.

Edit: Forgot to add that another reason this hurts him so much is his older sister still talks to their dad and he felt betrayed and though his mom was on his side. His parents were very emotional abusive before his dad did the things he did. He was treated worse than all the other kids and yeah he had trouble regulating his emotions but like his cousin said they never had the patience to help him learn how.