You seem to be missing the point of prayer...
to HELP SOMEONE...
to invest YOUR time, and YOUR energy, and YOUR good wishes on someone else.
To say that you won't waste your "precious" time on someone else sounds like you missed the meaning behind a prayer, anyway.
EDIT: and yes.. I AM married, and if I mess up by cheating, and asked for prayer, while I pray to fix the problems I have within myself (to save my marraige) then I would hope that others would, indeed, keep me in their prayers. Just because they (you.. I... whoever...) cheated, doesn't mean that they can't repent, and work to fix it.. and it doesn't mean that you can't pray to give them (the wife, and the husband) the much needed strength they will surely need to overcome such a disasterous event....
/EDIT
Ray
