Aita For blowing up about my now ex hiding a snapchat account from me?

for context we had both agreed she wouldn’t have one anymore after she used it to cheat on me with 2 different men while she was drunk.

i found it on accident and i did ask for the password which she reluctantly gave me and when i went through it she tried to hide that she was speaking to 2 different guys which led to her and i arguing however according to her she’s not cheating on me.

i feel insane.

would like to know reddits opinion