Yesterday I thought of someone in my past who insulted me. I indulged in a sort of fantasy about a clever way that I could have insulted him back. I repented after a few minutes, but since yesterday I have worn myself out thinking about whether or not this was a mortal sin. I do this sort of thing often with different thoughts, and this is killing me. I wear myself down wondering whether if it was a mortal sin. If I could just repent personally before God (provided I did it sincerely), there wouldn’t be such an issue. But mortal sin can only be forgiven in confession, and how practical is driving to town to go to confession several times during the week to confess my sins? I know there must be a better way, but I don’t know how to find it. Please help.