I know nothing of your financial status but it seems like you are spending an awful lot of money simply to "create" a relationship. Paying for sex is one thing, paying by the hour to have a woman simply spend time with you is, in my opinion, a serious waste of money and a stall tactic.
Clearly this woman will take as much of your money as you are willing to give her. That is, after all, her job. Is it a good idea? Honestly I don't think so. Be honest with yourself. Are you trying to make something happen with this particular lady? Do you have feelings for her or are you really just looking for company? For a number of reasons, including the concern about performance anxiety that you expressed, I think this is a bad idea.