i feel so lost

i apologize for not using the correct terms but i (24f) found out yesterday that my husband (25m) kissed another woman. we weren't having any problems in our relationship and he keeps saying he doesn't know why he did it. they were just meant to hang out that one time as friends but he never told me about her. he took her out to a nice restaurant that we had our first dating anniversary at (we've been together for over 3 1/2 years) and randomly kissed her. he immediately regretted it and drove her home. he kept it a secret in hopes of it just going away until the girl messaged me on instagram. it took 2 hours of talking before he confessed. some details of their stories don't fully match up and idk who or what to believe. he didn't come home until 2am the night it happened claiming he was stuck at work (not unusual) but i called him around 1am to make sure he was ok. i was worried he might've gotten into an accident on the way home or something. turns out he was with that girl and told her it was his boss calling instead of me. we have couples therapy scheduled and are planning to get individual therapy for him as well. i've been in therapy for 5 years and have a good support system. i kicked him out after i found out. he was so beside himself and upset and wants to do whatever it takes to fix things but there's a tiny part of me that's worried he's only upset because he got caught. we have NEVER had any issues like this in the past and he said it never happened after that single incident. he blocked her on everything immediately after he dropped her off as well.

i feel so stuck right now. i always thought cheating was black and white and i'd be able to leave right away but that is so far from the truth now. i keep going back and forth from forgiving him immediately or leaving all together. i want him to hold me and tell me everything is going to be ok but i also never want to see him again. i can't get the images of him kissing her out of my head and last night was full of nightmares. i still feel like i'm dreaming and i hope to wake up soon. he has been doing anything and everything i ask to make me comfortable. we have life360 now and he sends me picture updates of what he's doing throughout the day. he even offered to delete all social media if it would make me feel better. i want to believe him and trust him so bad. he's my safe space and i do love him but i'm worried i'll never get over this and be miserable if i stay. i don't know what to do. i don't know what to feel. no amount of distractions are taking the pain away. I've started drinking to try to take the edge off but i just feel so empty. i feel like i'm drowning. I'm so scared of being judged for staying and trying to work things out too. i want to believe he's being genuine and wanting to fix everything but i don't want to be hurt like this again down the road. I'm scared and feel so so alone right now. sorry for the long post. i needed to get all of that off my chest. writing things out helps me process ❤️‍🩹