AITAH for snooping and then being mad at my bf for lying

My bf (38m) and I (33f) have been together for 1-1/2 years. We have plans to move in together in 2 months.

A week ago, we were laying in bed and looking at reels on insta. He wanted to show me a reel that he had saved. He went into his saved posts and he hid his screen for a moment. I got the feeling that it was intentional and he had something to hide.

I have a bit of trauma from a previous relationship who would lie and do things behind my back. When I would bring up suspicions, he would shut it down and tell my nothing was going on. I should have asked my bf what he was hiding on the spot but I was convinced he would not tell me the truth and act like I was crazy.

I know it was wrong, but the next day I went on his insta and looked at his saved posts. He had a folder full of videos and pics of other women with huge tits and ass. Some were saved recently. It made me very uncomfortable and insecure. He even had saved pics of one of his female friends. But those pics were posted years ago. So he must have saved them long before we were together.

I was working out how to talk to him about this, when, a couple days later, we were laying in bed again looking at reels. He went in his saved posts again, but this time did not hide his screen. The folder with a half naked woman in it was at the top. He turned his back to me, started to get ready for bed, and was on his phone closing lights and stuff.

I told him I was upset for seeing a half naked woman on his phone. He said well it's just a video of someone weaving that he found interesting and she happens to have big boobs. I said oh yeah, show me. Well, in the 30 seconds he had his back turned, he had deleted the folder. And magically couldn't find the reel to show me. I was livid and couldn't believe he did that. He kept stating that the folder contained reels pertaining to hobbies & crafts. I kept accusing him of lying but didn't tell him I knew the truth. I asked him why the hell he would delete a whole folder if it contained innocent hobbies & crafts?? He said it was inappropriate to keep the folder with a half naked woman in it. I said well why not just delete that particular reel?? Or show me the folder so that I could see that it was innocent. He said he didn't think before acting.

On one side, I know I am in the wrong. I snooped. And then didn't tell him. Made him look like the one in the wrong and accused him of lying while being deceptive myself and trying to manipulate him to tell me the truth. I feel like an awful, hypocritical, childish person. I think deep down I was trying to test him. To see if I could really trust him. I was also scared of telling him I snooped and that he would end the relationship over this.

On the other side, I am hurt that he would have a folder of other women and that he would lie to me. If I hadn't snooped, I still would have been very suspicious just by the fact that he didn't waste 1 second to delete the folder. He would have lied to me and made me feel like I was crazy for being suspicious. Just like my ex would do. I would have gone crazy over wondering what the hell was in there.

And at the same time, I am like, it's just women on a screen... Am I really making a big deal and putting my relationship on the line over this???

I don't know how to move forward. I don't know if I am making a bigger deal out of this than I should. Should I tell him the truth about my own snooping and lying? And beg for forgiveness? Or am I allowed to be mad at him in this situation? I don't want my relationship to end.