My feelings on the situation are that you should go to school in Canada (be it U of S or somewhere else affordable). As hard as it will be staying in a LDR for 4 more years, I think it's way more reasonable to do than putting yourself 200,000x more in debt coming out of school. I also think that your parents definitely need to take the agreement; you guys have been dating for over a year now, this is obviously a serious relationship at this point and they need to respect that you guys need to see each other sometimes.
In terms of the college not being good enough for your degree to get you a job when you move to the states:
I don't know what you intend to study but I don't particularly think this will be a huge problem. Another thing is once you have a degree, if it really is an issue over in the states you can go back to school or get your masters/doctorate or whatever. Classes are transferable and you'd probably be able to get credit for most of the ones you took at U of S so you'd only need to go back for (at most) 2 years.
Big issues that hit me w/ moving to Washington:
-No medical insurance: As a person who gets sick a lot, this troubles me because medical bills are REALLY expensive. My ex (and current) boyfriend didn't have medical insurance and I know for a fact he really needs to go to a doctor he just can't afford it. That isn't something I would wish on anybody ever, because if you're sick you need to go to the doctor and you shouldn't have to worry about "Oh this is going to cost me 500 dollars" or something like that.
-Parents won't be happy: Ok, so, when I turned 18 I went off to University of Georgia and lived in the dorms, which my parents were very happy with. Got depressed, failed all my classes, dropped out, etc. and when I came back home I told them I wanted to move to California to go out there to live w/ Mito and go to school out there. Obviously they were not ok with this at all, they threatened to disown me and there was a lot of tension in my house for a very long time. In my mind all I wanted to do was be with him, and I didn't see how they couldn't understand. Well it took me a long, long time but I finally realized that I was being very irrational and impatient. What I believe (and this is me, I don't know how you feel on it) is that if you're going to be together then you will be together, and if two people put in the work then you can make it work no matter the distance. I should have realized that moving across the country to a place where I wouldn't have medical insurance, and my parents wouldn't speak to me or help me afford to live would have been a huge mistake. I do know that being apart from the person you love is incredibly difficult, and once again I wouldn't wish it on anyone, but thinking long term is way better than thinking in the now. Building the foundation to an affordable and livable life is super duper important.
My big problem with U of S
You never wanted to go there anyways:
From what I've heard, college is (supposed to be) the best time of your life, so I feel like regardless of where you go you need to go somewhere that you want to be, and this is INCREDIBLY important. As a person who dropped out of college because they didn't want to be there, i know how important it is to be in the right state of mind when going through something that takes as much work as college does. If you really have no interest in going to U of S, then I wouldn't even consider it an option. I wouldn't close your mind just yet, you still have some time to look at other schools so I would just keep your options open and see if there's anything else you can find that you like.
My ending thoughts are just that this is your decision, and I obviously can't make it for you (and I wouldn't want to, because only you know what's best for you). I'm not in your shoes and I've never lived your life so I can't for certain say how similar your situation is to what mine was at all, but just as an outsider looking in this is the advice I'd give. In the end I think you should definitely give a lot of thought to it (which I'm sure you already have and will continue to do), and you'll come out making the decision that's best for you. Just don't stress too much right now, you still have time.