Frustrated and confused

I've been with my partner for 10 yrs. Throughout our relationship he has been friends with his ex. They av no kids together. She has but he don't. 4 yrs ago i checked his phone when he was drunk and caught him and his ex flirting. I woke him up and asked him whats going on and said to him i thought u told me u guys were just close friends bcuz u guys didn't dated long only for a few months and both of u decided to just be friends and the fact she got her tube tied and he wanted children. Anyway he apologized and stupid me forgave him. After that he decided he wanted a fresh start and wanted to move to another State. He changed.his number and all. 2 months after we move i check his phone again and realize she has both of his new numbers and also her kids. I confronted him he said they weren't texting anything bad and they werent flirting let me say they were texting around 1am while i was in the room sleeping. I told him to block her then again of course he unblocked her again a few times. Now on fathers day i saw a package delivered to our home address and its from her kids saying happy fathers day, we love u and thank u for all that u done for us with her and her kids name at the bottom of the note. I got mad and now we are sleeping in different rooms and he keeps saying im overreacting. Please someone tell me am i really overreacting or does he not take me for the biggest fool and very disrespectful