I was ratted out by my ex-husband, who was stalking me at the time. He followed me around, even online, and found out I had a boyfriend. (We didn't have "Scriptural" reasons for divorce; obviously emotional abuse and his idea of fun in the bedroom, overpowering me, were not enough for the elders.) He went to the elders about it, and they came to see me. I suppose I could have denied it all, but I've always been one to tell the truth when confronted.
So when they asked if I had a sexual relationship with my then-boyfriend (now-husband), I said yes. When asked if I was planning on continuing it, I said yes. So I got DF'd.
If I had it to do over again, and had time to think (They showed up unannounced.), I may have lied my way through it and spun a good story just so my sister and brother could still talk to me. But then, I'd eventually have gotten DF'd anyway, because it became common knowledge that I was living with my boyfriend, and then we got married. So still without "Scriptural" reasons for divorce with the possibility of remarriage, I would have been DF'd.
That was a lot of talk for what could have been a very simple answer.