Was I blind?

So while my bf and I were together we had a fight and he asked for time to think. We did NOT break up. My friend texted me a screenshot of him on a dating app.. I confronted him when we mended things and he said “I didn’t talk to anyone, I didn’t cheat, I have never cheated on anyone. I thought we were done”. Whatever, I forgave him, fast forward.... he got distant, stopped texting me first and would only talk to me if I texted him first. He never answered my phone calls and only talked to me when he called or when it was on his time.

We broke up due to him literally putting no effort in anymore. He was NOT like that in the beginning. He is already on a dating app again..... and this whole time I’ve been trying to fix things with him while he’s been ignoring me, etc.

Like.. now I just have a weird feeling that he’s been on there the whole time???? Wtf.