Why is my guy friend so invested in my dating life?

I have this guy friend that often bring up my dating life. When I tell him I met someone he immediately starts telling me that I’m going to sleep with them or implies that they are using me for sex. I always ask him why he keeps talking about sex or bringing it up. He then starts to shame me into not dating and saying they are not a good fit or he will deliberately give me bad advice to Salvatore my dating life. I’m not attractive to my guy friend and only sees him as a friend. Why is my guy friend so invested in my dating life? Why does he care so much and try to slut shame me if I try to date anymore?

Why is my guy friend so invested in my dating life?
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