I 20M have serious trust and anxiety issues with my boyfriend 24M

So me ‘20M’ and my boyfriend ‘24M’ have been together for a couple weeks now. We met on tinder and we felt like there was chemistry and stuff, he gave me flowers, an expensive cologne and a book on our third ever date (it was a little after Valentine’s Day). We decided to be together after like 4 weeks. Right after that, he gets diagnosed with an std that I didn’t have (I tested negative) and he said that he didn’t know where that came from.

After that happened, I chose to take a step back and bring it back to the “talking stage” and agreed with my therapist that it was too early to expect commitment from this relationship.

We worked our way out of that to the point where I feel comfortable again with him and apparently he does too, I’ve met his family and he’s met my family and friends. I think he’s had actions that show real effort for this (early) relationship like he paid for all dinners with my friends and my family (I think he didn’t have to) he’s listened to my concerns about communication and worked on them, now he shares location with me (his idea), remembers details about what I tell him and most importantly I’ve told him what I’ve been through recently (self harm, suicide attempting, substance abuse, REALLY bad anxiety ) and he’s been very supportive, he even was open to keep talking to me after I got discharged from the mental facility. But thing is…. I still don’t trust him??? I pretty much feel comfortable around him when we’re together but for some reason I can’t end up trusting him.

I told him that I had really bad trust issues and he said that he understands if I don’t do it in a hundred percent, because we are still getting to know each other and that it was ok, and that’s when he pulled out the location sharing thing and said “I hope it helps”.

I don’t know if this is because I am aware that I’ve been with other guys while being with him and that he does the same too.

But why if I’m doing it it hurts to think he is doing it too?? We decided to be together again like 2 weeks ago and I really like him… but I don’t trust even tho he has not given me any signs of doing something.

I would appreciate any opinion or advice