I don't think your girlfriend is being unreasonable here. Between college and you establishing your career, that's an awfully long time to be put on the back burner.
I feel it's important to set aside personal time even in college and early in your career, otherwise you'll burn yourself out, or wind up with a mountain of stress. If you're still determined to focus all your energy in your career, perhaps you should go your separate ways so you can each find someone who has a more compatible lifestyle.
I'm a woman who hates when her fiancÚ spends too much time working so I'll talk like one. The question is, do you really want to sacrifice your relationship to achieve faster success at work? You are talented and hard-working so you will succeed sooner or later. The 'not-so-awesome' job in the gaming/film industry (but still in the industry you are interested in) is demeaning or what? Because I don't believe that you couldn't find any job with your skills. I admire your 3d skills and your passion for working and improvement, but it is something you can do over a years. We learn and improve all life. Personally I don't mind having a less prestigious job than I could have if I had spend more time on training. Maybe over the years I'll achieve something greater, but isn't building a happy relationship a biggest success? If you focus so hard only on your job, one day she might be gone and it may be to late... I also want to achieve a lot as an artist in the future, but I would never put my relationship in a second place. Is there a real reason why you are in such a hurry to become the best at all costs?
But if your question really is " Should I let the relationship fall apart and focus on my career" then I'll answer you with a question - do you really care about her if you consider breaking up to boost your career? Maybe she's just not the 'one'? Then go for your career... just don't miss her later - it was your decision...
If you want her to stick around, sit down and talk. Find some time for her.
If you want to focus on your career, give her the walking papers so you can both get on with your lives. It would be quite greedy of you to want her to sit around and wait for you to have more time down the line.
What else is there to say about it? Your girlfriend demands more time because she feels neglected, and you admit that she is neglected but that you find your career more important. And you're not inclined to do anything about this any time soon, not even after graduation. If you thought putting less time in your career was a viable option you would have put it on the table already, but it didn't even get a mention in the OP.
This doesn't mean either of you is the bad guy, her demands are perfectly reasonable and your ambitions are, as well. But they're not compatible, at least not at this moment.
Just because the girlfriend you have now feels that the amount of attention you can give her isn't enough for a relationship, that doesn't mean that's true of every girl and every relationship. If she's too demanding, she probably isn't the girl for you and your life and you can find someone else who is.
I don't think we can decide for you whether you should focus on your career or attempt to seek some balance. I personally feel that a balance would be best, but then it's difficult to achieve that sometimes, and maybe balance isn't for you. Only you can know that.
If you can't find a compromise with your girlfriend, perhaps it's time to end it now rather than later. It depends on what you're after and how you think you'll achieve it. I don't think it's healthy to constantly be working.. there should be time out where you're not all about work, otherwise you'll just burn out.
If you place your career/education/etc. in front of your girlfriend, you've got your answer there. If you balance things a bit more, it doesn't necessarily mean you get out of college as a second rate artist. Perhaps the matter is about time management. Maybe you can set a certain amount of time for work, both inside and outside the home, and then leave some time for other things.