I had sex with my BFF's brother

So I regret this so much, but I lost my V card to my bff/ basically sister's brother. We were at a party, and yup there was some drinking and I made a bad decision to have sex with him. After I told him it was a huge mistake and it can never happen again, but now every time I see him he's always wanting to do something. I will never give in because of how guilty it makes m feel around my bff. I can't believe I did that 😭😭😭😭. I'm still so mad at myself for it. Also he's 2 years older than me, and he will be 18 this year!

Ps. The legal consent age in Missouri is 14 so no comments on how I'm to young to be having sex, and this just happened last month and I'm almost 16. I didn't want to have sex until I was around 17 but like I said we were drinking and I wasn't thinking clearly 🤦🏼‍♀️🤦🏼‍♀️🤦🏼‍♀️🤦🏼‍♀️.