What type of friend would ask a man's wife out on a date?

My husband's so called ''good friend'' texted me on my messenger yesterday, asking me out on a date to the movies and then to eat on a restaurant, but just the two of us, that my husband doesn't need to know.

This was my reply back:

You're joking right? Are you ******* out of your mind?

He then kept telling me to calm down. Then started going off on how my husband can't give me kids, what's the point of staying, etc.

I was horrified at what I was reading. He was suppose to be one of my husband's closed and trusted friend. He knows why he can't ever father a child and yet he was using that against him on that message. Over the last couple weeks during reunions, he was acting a bit friendlier than usual but I didn't think anything other then just being cordial. Then it started getting weird whenever he would suddenly appear online whenever I was online. Now this message. I felt disgusted. I've already shown my husband and he proceeding to unfriending and blocking him. What type of friend does that?

Updates
+1 y
and he was upset afterwards and thinks I've ruined his friendship with my husband. He was upset after I showed my husband the message.
What type of friend would ask a man's wife out on a date?
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