Omg. Dude. Get yourself some therapy. Not for your kink, because, whatever on that. There are loads of people who are into feet, loads who are into urine, pornhub can confirm. The issue isn’t that you’re into feet. The issue isn’t that you’re into golden showers. For every kink out there, there are people who are more than receptive. The issue, which you are being willfully obtuse about, is that you did NOT have clear and enthusiastic consent. Period. You do NOT get to touch ANYONE without their expressed consent, ever. You don’t get to fulfill your sexual fantasies without the other person being fully onboard with it. What you did was sexual assault. You can continue with your ‘piss is natural’ until your fingers fall off from typing it. You did a thing, that you and only you, received gratification from. Your (ex)girlfriend feels rightfully violated. Until you can seek therapy, in order to fully understand boundaries and consent, never be in a relationship. Actually, just stay away from all persons who have the potential to be a sex partner, because, as of the moment, you’re incapable of understanding what consent means.