At least you're recognizing this now and not after she's moved in and bankrupted you. You obviously can't already plan on marrying someone you've never even dated in person (meaning lived in the same city and seen each other IRL all the time). So maybe tell her that she's welcome to move in but only once she's prepared to cover half of the bills. 30% is too low a bar if your goal is to make her prioritize and be responsible. For better or worse, a serious relationship is as much about mutual responsibility as it is about love. You can love someone to death but if they can't pull their own weight it won't work. Keep an open mind about this because if she never gets her act together you need to be willing to break up.