Hey girl: Really cant blame you for wanting to spread your wings... 18 is an age that you really start exploring who you are or what you could be.
If there is ONE THING i can tell you about you wanting to move out and be a free bird... its this.
DO NOT leave on bad terms. ( and this is why)
about 4 years ago i was in the same situation or similar as you. I decided i wanted to be out and about and free to be who i wanted and experience life. my dad was super strict which was so annoying...but we were REALLY REALLY CLOSE. Daddys girl to the extreme. anyways, finally one day he pissed me off beyond belief and i decided i was leaving. It was over a dumb fight.... and for a boy at the same time he didnt approve of.
Regardless of why, i moved out, despite his feelings and really it was in a moment of anger that i decided to leave.
4 years later... my dad and i still do not have a close relationship like we once did. and i really do regret doing things the way i did. It was silly and immature.
SOOOO....
all that to say, chose to make that move when you are thinking clearly and not running off bult up frustration and emotion.... its the worst thing you would do to yourself and your family!!
Now, that being said, moving out so young, really did allow me to grow up and mature to a point that many my age still are trying to get a grasp on. Good luck with your search for what is going to make you happiest and content.
Also.... tell that boyfriend you have better things to do than fight with him!!!!
hehehee jk girl im just messing with you... i know how it goes!!!!!

silly boys!! isnt it great though when they say the "right things" hehehe