Hello, RedPill community. I wanted to share my theory about why men often stay in relationships that are toxic and are baffled how this one crazy chick manages to stay in their lives for so long. It's really important to figure this out and be aware of your "weakness" to escape the doom loop. It's my first longer comment here, so if something is violating the groups rules, let me know about it. I also don't know if this is new information to you or common knowledge here, let me know about that too.

Certain self-destructive phenomena are overwhelmingly more common in men then in women. Excessive computer gaming, gambling addiction, speeding and - staying in a toxic relationship with a woman because she gives you sex. The latter being the main topic I want to talk about. I think most men can relate to that: You were in a relationship with a girl for a while, maybe for a few months or even for years. And this relationship wasn't one that your friends would consider "healthy" or "worth it". You complained about it in front of your buddies, you had a lot of fights, maybe it was even an "on-off" relationship, you sometimes felt terrible, overly stressed, it had a negative impact on your career, your hobbies, your social life etc. But for some reason that crazy chick that would start a fight out of nowhere, ruining your evening several times a week was somehow still worth it for you. Why? If you really think about it, it was mainly - the sex. I bet you could design a graph were the amount of distress men are willing to endure in a relationship was proportional to how hot the girl was. You would ditch her if she was a 4/10. A 5/10 would not annoy you any longer than maybe a few weeks. But this 8,5/10 you are with is really special and somehow your soulmate? Wrong. Your brain is "tricking" you into idealizing this relationship, but if you really think about it, there are just a few factors that make her special: Youth and fertility. The ideal girlfriend would also give you companionship, support and validation. But youth and fertility have the highest value for men. Let me explain each of those for you.

Youth: Young women are more likely to give birth to a healthy child then older women. Women "peak" at a certain age and after that, the risk for birth complications is significantly increasing.
Fertility: This factor deserves to be in a separate category. Youth does not automatically equal fertility, even though of course it's connected. Overweight and especially obese women for instance are much more likely to have pregnancy and birth complications, to give birth to a child with disabilities etc. By the way: Obese men have a certain chance to have no sperm in their ejaculate. So obese people in general aren't attractive to others unless long-term pornography use distorted their sexuality. Also, people with a low SMV, especially obese women, are likely to be in denial about it and lie to you about their preferences, telling you "looks don't matter", but they are just lying to themselves. There are a lot more factors, of course. On of which is the estrogen content in a woman's body. There is a study where researchers tested for a group of women's estrogen levels. Then they took pictures of the women's faces and put them into a high-estrogen and a low-estrogen group. With a software they combined all the faces of each group member and now had a generic high-estrogen and low-estrogen face. Then they asked people, men and women, who's more attractive and the majority agreed on the high-estrogen face. By the way, don't try that on your girlfriend, she'll pick the low-estrogen face cause it's less threatening to her.
Companionship: Men are actually happy when a woman is just around. Just her presence in your apartment, your bed, on a bicycle tour is enough to give you a certain amount of happiness. Having hot chicks around is always associated with pleasure for men.
Support: You are on a trip to Italy and she is taking pictures, cooks something delicious, she makes sure everything _around_ your interests and goals is appropriate. This is probably also a sign of a good mother.
Validation: Men want to impress women. Making her laugh, being admired, her horny look when she sees you in your sweaty shirt after the gym, those things make men happy.

Men are "r-selective" and women are "k-selective". What that means is that men go for quantity while women go for quality. There are some people in the manosphere that say woman have it better cause they can have as many men as they like. And that might be true. But they are projecting male mating strategies and preferences on women. For a men it's better to have 20 women in a year than 2, for a woman it's not. She would take 2 high-quality men over 20 mediocre but still attractive looking guys. Because she peaks for a short time and is therefor very selective. Men want to spread their DNA over as many women as possible as long as they are relatively attractive or at least have one good feature like big boobs or a cute smile.

Tomassi says men wouldn't value themselves enough and therefor stay in terrible relationships or make very poor decision and in part he is right. But it is more than that. Men - by nature's design - overrate youth and fertility. If she gives you crazy good sex, if she is a 7/10, that is what matters to you. There is even a difference in how men and women evaluate negative and positive experiences or events in a relationship. While women are more focused on the negative - she'll never forgive you for forgetting her birthday - men are focused on the positive site. Which is why men can forgive and forget more easily, women can't. When women are with a real jerk, maybe even a narcissist, they don't really "forget" how he is, it seems to be that they are with him _because_ he's like that. They are driven by emotional impact, be it negative or positive. Of course this is an oversimplification and a narcissist has to have certain alpha features (and honestly, they usually have) that attracts the woman. He can't just abuse her. But what I'm saying is that women evaluate negative and positive experience very differently from men.

So I'd argue it's sometimes so hard for men to leave a "crazy girl", cause our brains are more "r-selective". We'd rather push ourselves to the brink of exhaustion then giving up easily on a good and available source of pussy. The "slut" is more cheeky, cause she knows her powers. Women also stay in toxic relationships, just for different reasons.