Open relationship & why am I in it?

Husband was 18 & a romantic manipulative narcissistic british boy living in England. I was an American 35 yr old divorced mother of 3 , fresh out of a 16 yr abusive marriage ready to get my groove back and , over the internet, our worlds somehow collided & we married a year & a half after he came here in 1999.

Fast forward to now. After years of amazing travels, crazy sexual encounters, his aspirations to be a musician and then me being the only one working a hundred a hours a week to support 3 kids & his lifestyle , he says I've changed. I'm no longer the wild spontaneous wife who indulged this younger sociopathic husband. I'm 53. Hes 36. I've been tolerating his numerous relationships over all the years weve been together. I reasoned at first, that he's young, I can't hold him back. This man ,as my husband , moves heaven and earth to make sure I'm happy. Is it because I support him so he can do his thing? He swears he can't help the relationships. He's addicted to porn and I stopped sex with him years ago because the porn & his cheating ruined it for me. But he's not going without, but he says it breaks his heart that we don't. I think it hurts his ego.

anyway, he's been in a long distance relationship for last 5 years. She's become his sex toy. Lost 100lbs & prostitutes herself for him cos he likes it. He wants to split his time between me & her because she can support his fantasys and his music career & I allegedly have his heart. Can any1 explain my life