Should she tell?

Dear Diary,
So a friend of mine called me last night for advice. This is something that was weighing heavy on her chest and she needed a lil advice... I really wasnt sure what to tell her...
Her Story:
T was married at the time. She is now divorsed but not for the reason from this story. He husband worked 2nd shift and she first. So they didnt get to see much of each other during the week. Her neighbors (L) husband used to stop by and hang out with T in the evening or nights, especially after L went to sleep. Everything was cool. Then one night L's husband kissed T. They made out. Gropping was involved. That was it. That was the end of it. T made sure she was busy most of the time when L's husband would wanna stop by or anything. Years have passed. Both L and T are divorsed now and are very good friends. Back when the issue happened. They new each other, hung out from time to time, but werent super super close. Now T is trying to figure out if she should tell L about what happened with her husband YEARS ago or if she should just let it go. If she tells she might lose a friend. Cause more issues for L and her husband. L might go and tell T's ex-husband and then there will be issues there.

I am not really sure what to tell her.
Is she just wanting to tell L because of her own personal guilt she is feeling?
Is it worth telling T?
Will it make a difference to T that her husband cheated with her friend?

Your opinion?