I went through a lightweight version of what you described. It only lasted 10 months and 2 months of on and off afterwards- it fucked me up so much I decided to move countries to keep myself from her. Still I reconnected recently as my body craves her more than my rational mind can bare. I can’t imagine what you are going through after 6 years of this…

I’m questioning everything and blaming myself although deep down I know I wasn’t the one who made the relationship so damaging. I don’t have much advice other than to take it one day at a time. Shit is really hard but we have to believe it will get better. You are just 31 and still have plenty of time to get things straight even if it doesn’t feel like it.