My boyfriend has a serious addiction. What should I do next? [24F]

I recently discovered that my partner of three years has a serious addiction issue. I found out on New Year’s Eve when the girl he was last involved with texted him, sharing how much fun she had at a party and sending videos from a concert they attended. I've come to terms with his infidelity, and we've had many discussions about it, but it feels like he's still hiding things from me. I decided to go no contact because, despite his claims of being open and honest, I kept uncovering more secrets, and the weight of it all was overwhelming. The stress was affecting me so deeply that I felt like I was at my breaking point. In the weeks following our last argument, we attempted to research therapy options for both of us, but every time I mentioned it, he would change the topic or shower me with affection to distract me. I’ve always been understanding, which led to me falling into my people-pleasing tendencies — another reason I felt I had to leave. One positive step he took was sharing his location for tracking on “Find My,” but as soon as I left his house after our last heated discussion, he disabled it. Two weeks have passed, and I texted him a happy birthday message, expressing that I still care but need time to sort my feelings out. He responded that he understands and suggested we talk this weekend. However, I managed to access his Snapchat and discovered that he's planning to have dinner with yet another woman he started talking to right after I left. This dinner is set for the same day he wanted to talk. Now I’m faced with a dilemma: Should I confront him about this new situation, or simply move on? He expressed a willingness to seek therapy and had even looked up resources with me, but the lies have made it hard for me to trust him, which is why I stepped away before becoming too invested. I know this issue of mistrust will take time to heal, but I can’t help but question whether it’s worth it — should I throw my hands up and move on? I also have his mother’s contact information, and we’ve discussed the situation. Should I inform her about his date with this other woman, or handle it myself? Should I confront him again about what's going on or let it go? This decision is weighing heavily on me, and every time I think I have clarity, something new arises. I've found a therapist to help me, but my first appointment isn’t until next week. Should I let him go on this date to see what develops, or should I intervene and let everyone involved know what’s happening? This whole situation is incredibly frustrating!