So a few weeks ago my husband came home after being with his friends completely out of it and fell asleep (or passed out) on the bed. I checked his phone to try and find out what was wrong with him because I was genuinely scared he might have taken something dangerous. Turns out he had been taking drugs with his friends. I saw messages between him and his friends about "are we doing it tonight, who's got the "stuff", do you wanna share". The messages went back years to before we even met. I was completely unaware he did this as after 6 years married it's the first time he came home like this. He would always be abit "off" when he came home after being with his friends but he swore it was only because they were smoking around him.
To make matters worse I found old messages from before we were together to a woman who he previously claimed he just flirted with. The messages showed they were obviously in a relationship. There were also messages from last year where she messaged him to say her mother died and he said "he would always be there for her".
I confronted him in the morning and he denied all of it. He said the messages to his friends were just jokes. After hours of arguing he eventually he admitted to the drugs and says he was ashamed to tell me and won't do it again. About the other woman he says he was never in a relationship and was just saying things he didn't mean as he was young. About the recent messaging he says that was the only time they spoke since me and him got together and he was just being nice.
I can forgive the drugs as everyone makes mistakes but I feel as though I cant trust him because he lied so much. Also, I recently saw the other woman's CV on his laptop with the dates of when we were together meaning they were still in contact. I don't care if he was with her in the past but he just keeps saying they weren't together and he hasn't spoken to her since we got together.
Aibu to not trust him and not be able to just forget this and move on. We have kids together and he has always treated us all well.