How do I lose feelings for my best friend?

I'm very insecure and I pretty much guard my heart from anyone so I won't get hurt and if someone would ever notice I will always just joke about it.

I have a really bad past with any guy but still I have this one guy friend, he's so so nice to me and funny and it very shocking for me to have that kind off affection towards me and people will sometimes say that he likes me and I always just laugh or make a joke about it when really I just want to tear up and say "really?".

I pretty sure he doesn't like me that way because he is seeing this one girl now but he doesn't seem interested in talking about her or answer my questions about her.

I don't want to like anyone because it's a 99% chance they won't like me back, it's always been like that.

still, I get jealous and I hate it.
It's a horrible feeling and it just kind off change me in a way.
I don't get mad I get sad.
She's really beautiful, nice and has the same interest like him so I understand why he likes her.

I don't want to feel like this, how can I get over him? how can I lose my feelings for him?
How do I lose feelings for my best friend?
Add Opinion