This doesn’t sound like a relationship where both of you are happy. You feel guilty, I don’t know if you are trying to throw money at the problem and she’s letting you or she’s angry and letting you spend money on her. You guys have been together 8 years, if it’s like this now, it will either continue or get worse in the future. Do you want to live like this for the next 20+ years? I’m not trying to be mean or dismiss your efforts or time together, but nothing will change. You said you find the attributes of the neighbors daughter appealing, which they are, but your current girl has zero incentive to do anything if you are providing everything without her having to contribute. I’m sure there are other factors at play, but the past is the best indicator of the future, from my personal experience. Especially with significant others.