Op, been in your shoes so I know exactly how it is. For anyone saying fdb etc etc, how can you blame the girl ? No one wants to live a crappy life. When you're younger than looks and all that can overcome a lot of things, but once a girl reaches mid to late 20's she is looking to settle down and find a husband. If you keep wasting her time then it'll just make it harder on her to find a quality guy once she's out of her "prime" and she'll be seen as a "leftover" and something must be wrong with her type. She's probably had external factors pulling at her too like friends, family and other potential dudes trying to get at her by talking down about you and your "career". At least she has the decency to give you this warning and hoping you can change for the betterment of the relationship. She could've easily just peace'd out on you but she still wants to be with you in the long run if you can change. From previous experience, there are a lot of tyrone's lurking in the shadows right now talking in her ear and acting like sharks circling the waters like there is fresh blood. At this point you have to decide if what your doing and how you're living is what you want out of life. Otherwise you gotta shape up and do what you gotta do if you see her as your future wife.
Good luck op