FWB & Defensive

I’ve been sleeping with a guy for awhile. We’ve never been committed and the whole family life always took over. He has 3 kids and I have 1. Recently things have gotten somewhat “routine”. His parents are my neighbors so we see each other daily. He comes to my house for dinner. Will occasionally stay the night. Sometimes I’ll stay the night with him all depending on when we have our kids. I used to babysit his kids when they were younger, started 6+ years ago. (Hes 10 years older than me). So his kids are like my own. My daughter is almost 2 and unfortunately he’s around so much that sometimes she says he’s daddy. So the situation is funky. Since October 2020 we’ve only slept with each other. There’s a girl he used to hang out with and kinda string along but they haven’t had sex in about a year now. She’s now somehow related by marriage (his aunt remarried to a man and it’s the mans 2nd cousin) so today he told me he was in the shower at his parents house when I asked to borrow a thermometer (at 8:15am). Tonight my daughter called him and he texted asking why I called but I had no clue my daughter called. He sent me a screenshot where my call was showing but everything else blurred out. Minus the fact I could read through his blurring. He called this girl on Snapchat as a video call at 8:16am. Sooo one minute after he told me he was showering. I automatically assume he touched himself on the call with her. If he wants to do that then ok he can. But tonight while laying on my couch with him i casually made a comment about how he wasted it all on his shower call with her this morning. He immediately got defensive and swore up and down that he didn’t do that. Then he says if he told me why he called I wouldn’t believe him anyways. So I’m sitting here laughing because whatever if you wanna do that fine. Like it’s been a long time and nothing has happened between him and I so I fully expect him to do his thing. I’m content right now. But the defensiveness. Like just stop.