FlowersAndShit - are you ok? Has anything happened to prompt this post today or is this just a general reflection? I hope you're ok. 
I am in a LTR (not married) and have been for years. It is my third relationship. It is the only one I've been in that is what I always hoped a relationship would be. He is kind, considerate, always doing thoughtful little things for me and trying to make my life easier, while also making me laugh, having fun with me, encouraging me to grow as an individual, and still turning me on in the bedroom. It is possible to have a wonderful relationship.
I was fortunate to grow up in a happy family where my parents also adored each other and whose relationship was characterised by affection and respect. I think that goes a long way towards drawing the line of acceptable and unacceptable behaviour in relationships. I ended my first two relationships because I knew what relationships could be and recognised that those weren't meeting that standard (the second was abusive).
I also think knowing yourself is a vital part of it. I spent many years single after the end of my second relationship, putting myself (and my DC) first. During that time I retrained for a better career, developed new friendships and hobbies and basically built the life I wanted. I learned a huge amount about myself in the process, which in turn helped me establish much more clearly in my own mind what I did and didn't want from a relationship - although I also came to realise that actually I'd rather be on my own than in a relationship that didn't live up to expectations. Being single can be great!
When I met DP, we took it very slow and I made it very clear early on what I would and would not accept. He said he loved the fact I was so direct and he knew where he stood. We have both learned the art of airing any disagreements/issues before they become flashpoints and always listening to each other's POVs and respecting it even if we disagree with it. We haven't yet found something we can't come to an agreement on.
To some extent, I think you have a point. Given that so many marriages fail and of the ones that go the distance, there's a good chance that a lot of them are unhappy for various reasons, I think as a society we should accept that the traditional nuclear family is not the fantastic model it's always been held up to be. It has always benefitted men far more than women, and it's no surprise to me that study after study has shown that married men but single women are the ones with the higher happiness ratings. To me that reflects inequality. I think in an equal, happy, respectful relationship, the married women's happiness would be the same as the single woman's.
The point of this is that there are good men out there - a lot of them in fact. Unfortunately, recognising them is a skill that requires learning and you also need to have a lot of self-awareness about your own strengths/weaknesses.