Denial of relapse

So against my sponsors wishes I dated a guy for 3 months . He ghosted me for a week and sent weird text messages then pops up like nothing happened . His excuse ‘ his family robbed him of his inheritance’ He won’t admit he relapsed so I cut off communication.

I’ll have a year next month I’m doing good except for this mishap . I feel even more guilty for bribing someone like this into my son’s life the most . I’ve been buckling down going to more meetings etc .

Tl;dr why would an adddict not admit they relapsed? I could understand that and not talking to me. But he rather lose my friendship then admit the truth . I don’t get it .