I slept with my friend's mom last night

So I'm sure half of you will say you don't believe me, but whatever. Believe what you want. So last week I matched with this older woman on tinder (she's 48 I'm 27) and I started messaging her since she is pretty hot. She tells me to come over to her house last night so I decided what the hell. I get over there and we start drinking some wine and talking. Eventually she mentions that she's married which I did not know. She says her husband is away on a business trip and she kept trying to reassure me saying that she had caught him cheating on her multiple times. Then she mentions she has a son about my age and tells me his name and at that moment I realized I had a friend with that first name and last name. I started to panic a little bit so I asked where the bathroom was and while she was walking me over there I saw a picture of my friend on the wall. At this point I'm freaking out in the bathroom not knowing what to do, but I decided I would play it cool, keep drinking wine for a bit, then try to find a reason to leave. Well that's not really what happened. We drank for another couple hours, watched a movie, and I was getting pretty drunk. Before I knew what was happening she started feeling me and we were kissing and I think you know what happened next. I instantly felt like shite afterwards and I wanted to leave but I was way too drunk to drive. I ended up spending the night and leaving early this morning. To clarify, I met this friend in college and we still hang out semi regularly and I feel absolutely terrible about it. I don't think I can ever look him in the eyes again