<human>: Could you distill the essence of the text into 1-3 sentences?

I don't think I have a crazy sexul past but I do have much more experience than my SO. When we first got together he flipped out when I told him that I had been sleeping with one of my guy friends off and on w/ in the last 6 months of meeting him (my SO). He acted totally immature and from then on I sorta knew to tread lightly when talking about my past. Fast forward to (maybe?) a few months ahead... 

We had been day drinking and I don't know how it came up but I told him that my best friend and I had had some threesomes together before (at that point a few years ago). And he flipped out again, we had to immeditely leave where we were and the day was ruined. He was quiet the whole way home and I was left feeling like I had done something wrong... So we finally get home and we start talking. Again this is 5+ years ago so I don't remember the details that clearly... but he was on top of me (not in an aggressive way) and asking me questions... The last one he asked was did you sleep with John? (my best friends now husband) And I straight up said no... and that was the lie... For one it's not something I'm proud of, it was a terrible terrible hook up and it nearly ended our friendship. I felt it was my secret to keep and especially w/ how he behaved about my past I didn't want him to flip out anymore over my past... 

So now we are talking about moving, which means moving closer to my best friend so we would definitley see them more than once every other year and I'm just worried about the "what if". What if for some reason some way he finds out and throws a fit? And 
I do feel guility not being 100% honest about my past. So my question is, is this my secret to keep or should I come clean now and deal with the consequences regardless of the outcome?
<bot>: Do I come clean about a lie I told my SO of 6 years about my sexual past or is it my secret to keep?