I (29F), have BPD along with several other mental illnesses. My BF (27M) usually does well with my mental health. My BPD makes me overthink and over analyze every little detail. I am in therapy and working on finding the right meds for me, so for the past few months we have been communicating and doing very well. Before I got help was another story, things were rough but we managed. Well last night he randomly got up and went to check on our cat and her litter of kittens, no big deal. I got finished with the mob I was killing on the game and decided to go check things out also. As I was coming down the hallway I saw him typing on Snapchat and when he heard me he closed it fast and switched to Facebook. I asked what he just closed and he said he just posted the kittens to his story. I said I saw him typing in a message and he denied it again. I asked him to go to his Snapchat and there was a message from a girl about the kittens, and he went to the messages screen and there was another. I walked off to cool down before I went from 0-100 over nothing, so I went outside to do some of the calming techniques I have learned. He came out and explained it was nothing just ppl responding to the cute kittens. I asked why he initially lied and said he was posting a story when I saw him talking to the girl that was in the message right when he opened the app. He said he panicked and didn't want me to overreact like I have always done. Here's the thing, I understand that if you post pictures of kittens people are going to respond. I would have been cool with "I posted on my Snapchat story and these girls responded". But he lied, and I feel a little like he was using my past against me. I haven't blown up or accused him of anything in over 7-8 months. Hell, his ex has sent him friend requests over and over, and he has gotten random messages from old friends and I didn't react negatively. I know he probably has a fear still from me in the past but I just can't tell if he is right to have lied or if he is messing with my head or if I'm just overthinking.