Should I intervene in this situation?

My best friend (37M) “Harry” cheated on his girlfriend with one of our mutual friends (31F) “Myra”. Myra was unaware of the fact that Harry was in a relationship because he lied and told her that he was single. Myra was upfront about the fact that she was looking for a relationship, but he told her that he wasn’t looking for anything serious after they slept together.

Myra somehow found out that Harry was already involved with someone else and she also wasn’t willing to be in a friends with benefits scenario, so she blocked Harry and completely went MIA for months. Harry pretty much started stalking her for months. Myra came to my birthday party and Harry is trying to force Myra to be friends with him (complaining that she is being awkward and saying that because they have mutual friends that they should remain friends) although it is clear that she is avoiding him. Myra is polite to Harry, Harry wants things to be like it used to. Myra has told him to focus on his relationship, but he keeps bothering her.

I’ve tried to stay out of this, but should I intervene?
Should I intervene in this situation?
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