what is considered sexual assault...

About 3 years ago I was at a Halloween party with my fiancé (now husband) and my brother in law at his gf's (now ex) house. Everyone was pretty drunk, I am not a drinker so I wasn't all that drunk, just having some fun. Around 1:30 things got out of hand.. My husband and his brother were arguing and I was avoiding the argument and decided to lay down on the couch. Then he walks in, the gf's dad (party was at there house) he was being nice and asked if I wanted a blanket and I said sure, then he sat down where I was laying and just started to touch me down there... I stopped him and asked him what the hell he was doing. His wife saw everything and just walked away... She told me not to yell. He got up and told me he was getting a "vibe" from me all night.. I would never cheat on my husband, I love him more then anything in this world. We left. I tried telling my husband what happened but I just felt dirty and couldn't talk about it... I never considered it sexual assault because he didn't actually try to have sex but I needed to get this off my chest.... Would you consider what happened to me as sexual abuse or am I just overthinking it?