My (23M) girlfriends (23F) male friend makes me uncomfortable

*TL;DR Long story short, my girlfriend has a male friend she has been friends with her whole life. They had a sexual relationship together before we dated. He calls & FaceTimes her everyday & constantly asks to see her. I don’t like it.
I’ve been dating this girl for a lil under a year now. For the most part, the relationship is thriving. We both have similar goals, we talk constantly about our futures & share the same love for each other. Let me say, it’s easily one of the best relationships I’ve ever had & I cherish it. But there’s something that makes me feel a bit unsettled; her 29 year old male “best friendâ€. Let me add, I don’t have any close female friends & I have no issue with women being friends with guys while in a relationship & my girlfriend does have other male friends that are respectful but this one is...pushing a boundary, IMO. Recently, while I was with her, he FaceTimed her & even though I usually don’t listen or pay attention to her calls, I sort of listened in (I was in her room laying next to her so I kind of had no choice). The call isn’t the issue but the “joke†her friend made during the call is what had me stuck. Behind their laughter & teasing together, I overheard him say “if you come over here to see me, you’re going to be a ‘cheating’ girlfriend (hahahehe)â€. At that point, I was suspicious of his motives. My girlfriend knew I heard it so she kind of laughed it off & he proceeded to repeat it. They eventually ended the call & I brought the joke to my girlfriends attention. She claims that they don’t usually joke like that & that she didn’t expect him to say that. Bottom line, she didn’t really see any issue in what he said. We argued. Since then, this dude has been texting & calling her almost everyday. We would literally be out enjoying each other’s company, having dinner, etc. & he would call & she would answer just to talk about completely nothing. One night she told me that he called her & “confessed†his feelings to her, stating that he misses her, wants to see her & that he wished they had something more back when they had their sexual fling. This once again put a bad taste in my mouth. Recently we argued about it & I told her to stop speaking to him. She claims that I’m not being fair & that I’m giving her friend “too much thoughtâ€. I’m trying my hardest to not come off to her as being insecure, controlling or emotionally abusive but I’m just not feeling that friendship & I really don’t want to end a relationship with someone I’m in love with over this.
Sorry to keep you all long but my question to you guys is: Am I wrong/insecure for feeling this way? Am I wrong for telling her to not speak to him?


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