The first dictionary definition of "utility" is: the state of being useful, profitable, or beneficial.
If she's not chatting with you then it's because she is either not interested in you or because you are not adding utility to her life. So your options are to add utility to her life, in which case, she will recognize that and then will further use you to her advantage and in all likelihood, you won't get anything really meaningful in return. Or, you just totally ignore her and let her say hi or bye to you. If she does say hi or bye back to you, then simply not to be rude, you only say hi or bye back and keep moving. I can assure you that she only says hi or bye to you so that she doesn't look rude. My point being, is that one way or another you are never going to get anywhere with her unless you have a lot of money and are willing to spend it on her. Let's say you come into money, when the day comes that you either don't want to spend anymore money on her or you run out of money, then mark my words, she will move on and leave you behind. Other than that she will only seek the attention of men she is interested in, or men who she thinks will willingly add utility to her life (see 2nd sentence of this paragraph). That's just the way it is. It took me over 50 years to figure that out. I wish I had know this when I was 30 years younger. Good luck.