Should I reach out to his girlfriend?

I met this guy through work and a while back we we hooked up twice. It wasn’t anything serious, just fun. Come to find out he had a girlfriend when we hooked up.

I quit talking to him, but he kept reaching out to me. He’d always do it as if he had a work question then try to turn it into dirty talk. Each time I’d ask him how his girlfriend was and find out they’re still together, so I’d basically tell him that’s not cool to do to her be a better man.

A few nights ago I had a kind of urgent work question (long story just know it was important), so I texted him to ask the question. He then messages me on Facebook and asked me not to text him anymore because his girlfriend saw and they got in a huge fight. He said they’re trying to mend their relationship and that requires cutting me out of his life (as if I’m the problem???).

I didn’t respond to that and deleted his number. His girlfriend is now trying to add me on Facebook and even visited my LinkedIn profile???

I kind of want to reach out to her and basically say “hey I’m not a threat, absolutely do not worry about me, I hope all goes well for you” but I don’t want to get involved in their drama, and I certainly don’t want to hurt her in any way.

I’m a die hard girls girl and don’t want this girl feeling bad because of me.

Thoughts on reaching out to her?