Denise, you have to do what you feel is best. Don't analyze it so much. Sit on it for awhile. If after a couple of days, you decide maybe you overreacted, you can always discuss it with BK. Chuck and I have made bad / rash decisions in the past. When we calmed down and realized it, we just discussed it with the kids and let them know that even adults don't always make the right choice.
I won't say you made a wrong choice. That is something that only you really know. I do want to say that as the kids grow you want to be careful about not letting them be friends with others. As they get older, they tend to gravitate to those that they are "forbidden" to be around. My girls both had inappropriate friends that I worried about. Instead of forbidding them, I just made sure that I was very involved with the friends and showed them what was appropriate and what was not. The girls and I would talk about what was not allowed in our house and they were made responsible for having their friends follow the rules. That way we kept the communication channels open with the girls and always knew what they were doing with these inappropriate friends. My best friend when I was in middle school was not a good person when we first started hanging out. My mom and dad did the same thing and she was a different person with my family than others saw.
Now, telling you all that, I don't want you thinking that I think you made a wrong choice on this. That was not the reason for giving you the info. You just seem to be upsetting yourself over the decision and wanted to give you some other perspectives to see if it helps.
Also, prayers and

for John. Try not to think about what the worst things could be. Think about the not so bad stuff that it could be. Wrap your mind around that.