Does anyone else just feel such a lack of motivation to eat right??

I don't struggle so much with working out but I have a hard time really getting into healthy eating habits. My family isn't just unsupportive or anything, but the fact that I'm alone on my journey in my house makes it difficult. I live with my parents and they buy the groceries so even though they are really good about getting me fruits and yogurt and healthy snacks, they get all the unhealthy things that I've grown up loving still. So I see them and want them and usually end up eating them. I crave sugar so badly and give in almost everytime. Then I end up feeling bad because I ruined my goal for the day. I start over the next day and do the same thing. I have gotten myself into a cycle that I can't figure out how to get out of. I guess it has a lot to do with habits and routines so maybe if I could just discipline myself for a couple weeks it would be easier, but I can't seem to get started..

Any advice?