Look man, no one is gonna tell you how to get a married lady to cheat with you. It also sounds like you are fetishizing this married lady simply for being Japanese. My guess is she is the only target of your fetishization around, so you latched on to her like a lost and horny puppy. On top of that it sounds like you are being an annoyance -- hence her telling you to "not annoy" her.

Why are you so invested in being "friends" with a 51yo married lady anyway? Red flags all around, bro. How the hell are you feeling "betrayed?" Also what do you mean she has what you are looking for? What? Being Japanese? Dude, it's a married lady old enough to be your mother.

Walk away, go look in the mirror and be honest to yourself about your intentions. Maybe she is the one that feels betrayed because you are trying to get to get into a relationship with her -- a married woman.

Think about it, you probably asked her directly "you wouldn't ghost me, right?" Or something else like that. Gives off mad stalker vibes. If my wife was being hounded by a dude she met at the gym, I'd probably tell her to cut off all communication, and if he didn't stop, I'd definitely take matters into my own hands.

By the way, did I mention she's married.