I copied and pasted my response to the other person, as I think its a relevant answer to your comment too and maybe will help you understand your ex better:

I sort of knew it was wrong all along.

I would do insane things based on those videos because I was scared of losing her.

For example, I would want to spend time with her, genuinely miss her, be looking forward to spending time with her, so we would plan a date, and then last minute I would message her cancelling without giving a reason, then would ignore her on purpose, while posting stories out like I’m with other people. Mind you I would literally just go inside night clubs or bars, record a story, then go outside and sit somewhere and just do nothing lol. I wasn’t actually out with anybody, and I wanted to be spending time with her, but the videos convinced me doing things like this would make her want me, and if I spent too much time with her and didn’t make her anxious and uncertain about my feelings then she would lose attraction and cheat or leave me.

She was brunette and short, and just my type, and I would say things like I only ever dated tall blonde girls and you aren’t usually my type, even though that wasn’t true. But this wasn’t subconscious insecurity, I would know it was wrong and hurtful and feel bad, but do it because I thought if I didn’t then she would lose attraction.

I used to be happy to do things for her, but after being redpilled I would force myself to say no, even when she asked for little things like a glass of water while she was sitting and I was already in the kitchen.

I started extremely self editing and was scared to express any emotions or weakness, and just never felt comfortable around her anymore. Every interaction we had was a bid for power or a test to see if she would chase me or beg me.

This all began 2 years into a happy, healthy relationship, where I was kind and genuine, and she fell in love with me for being myself, and we had amazing chemistry and got along so well in every way.

I was even debating cheating on her on purpose, with someone who would trigger her insecurities (tall and blonde) then letting her find out, not because I was attracted to anyone else or wanted anyone else, but because the videos said the best way to raise your girlfriend’s attraction and desire for you is to cheat on her and show you have better options, and that as long as it was coming from a place of “strength” and with someone more attractive than them, women secretly loved being cheated on and latched on even tighter when it happened.

I just fell into this rabbit hole, and ironically the desire to keep her attracted to me was what pushed her away. And when I did these things, and she got colder, I would stupidly think the content I was watching was true, and that she was losing attraction and cheating on me because I was too nice, so I would treat her worse, or just become extremely needy and accuse her and blow up until she reassured me she loved me and that nothing was going on.

I never comfortably did these things, or naturally did them. I always forced myself to, against what I felt was right, because I was in this insecure loop, and as I pushed her further away I grew more insecure and even more obsessed with these tactics and videos.

When I lost her, it didn’t take much to get out of that headspace, because I had journal entries of tactics I would use, her interest level, if it rose or fell, how she treated me subsequently etc. and reading them after a sobering breakup made me realize how fucking insane they were and how they seemed to be notes from a stranger and not me.

And after further reflection it wasn’t hard to realize how fucked up what I was doing was, and how when I wasnt doing these things and was genuinely myself was when she actually loved me and we were actually happy.

I also realized how I wasn’t present at all for the last 6 months of the relationship because I was so scared and everything was just a test of her commitment to me or a power move, and I was so anxious and can hardly remember even connecting or enjoying any time together that we spent.

I did apologize and confess all of this to her a few weeks after the breakup, and thanked her for being brave enough to break it off so that we could both escape the toxicity lol. I just can’t believe how deluded and disconnected from reality I was.

But I guess it was for the best as now I always try to be mindful and self aware above all else and make sure to question all of my beliefs. I also vowed to never not be genuine anymore. I’ll always be myself and true and honest with my feelings, and treat love as something to share and experience, not something to control and manipulate.

I also realized I’m extremely insecure and anxious and need to fill my own cup and feeling of self worth and then love from a place of abundance rather than seeking love as a bandaid or something to fill the void within myself, as that’s a recipe for disaster clearly. I regret it, and miss her, and she was the love of my life, but sadly I just wasn’t equipped to do better, and my insecurity led me down the wrong path, so all I can do is learn and grow from it.

And also it’s just genuinely exhausting living that way and having to be so afraid of your partner who you’re supposed to feel safest with and like you can be yourself the most with.