Most Helpful Guy
I think you rushed to get married and that things weren't ideal even when you said your vows. For you to "fall" for your guy friend so quick and easily shows that you didn't love her husband as much as you shouldn't have or that bond couldn't be broken by someone you see constantly.
Also your "best friend" is a phony. To use the poor timing of your issues to state is "love" which could have been long ago shows what kind of person he is.
I think you shouldn't make this decision yourself. You should put it all on the table and tell your husband you had an affair and then see how he wants to proceed.