Mom threatens to sabotage my relationships

Alright so I have a date planned for new year's, a dinner date to be exact. I'm going go be 18 in a few months and my mom wants me to date....

Guys that she approves of by finding them attractive. Yep, what she finds attractive, not me. She wants me to talk to guys but then it's almost like she doesn't want me to get into a serious relationship so she will basically threaten to sabotage it by saying that she's going to text them or whatever (she can get phone numbers that me and my sisters are texting).

I actually want this one to go somewhere because we both came to the agreement that if all went well then the relationship status would move on to the next level and I actually want it too because he's a sweetheart, he spoils me and he said that if she didn't let me go he was going to fight her (not physically, he's already 50/50 aware of the home environment that I'm in). Anyways I know that if I say hey mom is it alright if I go on a dinner date on new year's she's more than likely going to say no and get snarky about it like she did when we were supposed to go out to eat tonight but something came up. I really don't know how to deal with this as I've never been on an actual date before because I've never been allowed so I just haven't bothered talking to people. I don't know, I turn 18 in April and he's probably going to take me out somewhere or let me move in with him and I guess she really can't do anything then since I'll be an adult.