Bf hooked up while we were in talking phase

The guy I’m dating now just told me he hooked up with someone while we were still chatting and in talking phase. We met soon after this and he says he hasn’t slept with anyone since. I get it that it’s not cheating. He doesn’t owe me loyalty. But, he says he’s not the kind who looks for hookups. And our chats have been quite romantic before we met. I’m having a hard time trusting him, and finding closure. It’s either he didn’t sense potential in our chats and was ready to hookup or he’s just the kind of guy who hooks up when he can. I’m having trouble processing this.

For context: we chatted for hours on end. And he had to travel for a personal family issue. And was out of town for a month. He kept in touch while he was away and we were looking to meet soon after he’s back. He hooked up the day he came back with someone else.