Am I being controlling?

My fiancé has a new female friend from work that he’s been messaging for a few weeks now. We made an agreement a week or so ago about him only talking to her at work and staying off his phone at home so he can focus on his family and because I don’t know her or trust her and I don’t see the reason for talking to another female everyday other than your wife. I don’t care that he has female friends but I know all the other ones and they’ve been friends for years versus a few weeks. It’s causing a lot of issues for us because he sees it as a control and mistrust of him so he stands his ground on he should be free to talk to whoever but I don’t trust her. I do feel like she says some stuff that’s flirty like if she does him a favor at work she says that he better love her for it or tells him she would be sad if they weren’t friends anymore. I know he would never cheat on me but the fact that he can’t refrain from replying to her on his off days (three days a week) is a red flag to me. Am I being crazy?

if I’m being crazy or controlling then I genuinely want to know so I can work on those issues but this has been a boundary of mine since before we got serious. I’ve always been a firm believer that men and women can’t JUST be friends and that if they weren’t your friend before us then they shouldn’t be a friend after us.

Am I being controlling?
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