Need advice. My partner helped raise two girls(not his) for 7 years in a former abusive relationship. They are now both adults in their early 20’s living on their own. My partner had a final falling out with their mom over 2 years ago, so they don’t speak at all. However, my partner is very touchy about the kids he considers to be his, and they have never really taken to me, nor do they treat him very well. Now for the last 6 months, I have caught him several times lying about being at “work”, but he’s really spending time with one of the “girls”. To be clear, I have no problems with him spending time with his step kids, I just have problems with the completely unnecessary lies to coverup what shouldn’t be a secret. I have tried to talk to him about it, how it makes me feel terrible that my partner feels he has to lie about one of the “most important parts of his life”. But he won’t even let me get that last thought out before flying off the handle- any mention of his stepkids can cause bouts of instant screaming and threats. Makes me wonder what else he lies about.

So it just happened again today. He said he was going to work this morning, then came home after two hours and told me some long complicated story about not being able to go to work because there was a marathon blocking the way. The he left his phone on the table and I see a message from his step kid come in saying thanks for breakfast. He doesn't know yet that I know he lied again, but I am fucking furious. I don't know how to handle this or bring up such a sensitive issue..... I have been in long term relationships with men with children before and have never had to deal with a situation like this before.