A woman I know has recently got engaged for the 6th time. She's mid 30's and this current engagement is to the same guy as engagement number 5.
I don't know her super well and haven't seen her since the pandemic but we have a close mutual friend and are friends on social media.
Our mutual friend told me that they met on a dating app in Summer 2020 and in October 2020 he moved into her flat and they converted her spare room for his children who stay at the weekend. They got engaged in March 2021. Our mutual friend had a breakup due to infidelity and when confiding in this woman, this woman admitted that actually between him moving in and proposing, she discovered he was still on dating apps and exchanging naked photos with other women. She explained that they had a fight about it but they were now on good terms.
August 2021, she finds out that he is doing more than just messaging on these sites. He's still on/rejoined and has been meeting up with and having sex with multiple women. He cried, apologised, begged for forgiveness but she threw him out. In October she took him back, he proposed again and she accepted. Not sure of the ins and outs since then.
I am a single woman and have recently joined some dating sites and he has messaged me. It's 100% him. I started some light conversation and he mentioned his kids and I asked when his most recent relationship ended and he said August 2021. I checked the woman's Instagram page and as of three days ago he was #LoveOfHerLife.
Do I:
a) tell her
b) tell our mutual friend
c) keep my nose out of an obviously chaotic relationship?