I find it interesting that he went a year without talking with them. And within a week of reconnecting with them he's planned a trip to Amsterdam and one of them is moving in with him? I find that a bit strange.

About him wanting to reconnect with friends after a year? Honestly, that's understandable, people change - after all, you believed more than once that he changed. If they reconnected and treated you respectfully it would be alright.

However, seeing as he already has a pattern, I wouldn't trust him either.

And quite frankly, his behavior and treatment of you after you didn't talk for a week? Seems very manipulative to me - he's taken that week of being angry as a way to force you into accepting it his way without even having a real discussion with you.