NC for this. DS is 19 and lives at home, he’s been with his GF for a year now. She still comes over to stay maybe 2/3 nights a week as she has since the relationship started. However, over the last couple of weeks there’s this lad from DS’s work who’s been coming round on nights his GF isn’t there and I’m fairly sure he and DS are sleeping together. There’s been a few times I’ve heard things when they thought I was asleep or the other night I peaked through the door and saw them both asleep in the same bed. I don’t care if DS is straight, gay, bi etc or even if he wants this lad to be his BF. Where my concern comes is that the GF is still coming round some nights none the wiser. I feel complicit that I know and haven’t said anything but also I don’t want to get any more involved than I already am. I haven’t actually confronted DS about this either as I don’t want to force him to tell me something he’s not ready to. So AIBU if I continue to turn a blind eye to this and just let DS work through whatever this triangle is himself.