Lacking the feeling of abundance makes us change who we are and can even make us sacrifice our values. We will literally do anything to be loved including changing who we are.
Inner Game: Abundance Part 1 by Braddock
When you meet a guy or girl who has a strong sense of who they are and doesn't seem to compromise there values or character in any situation or around any person, this is almost always because they have a strong feeling of abundance in their life.
When you have great friends, you will do very little to impress new people and are damn sure not willing to do or say something that goes against your character. You don't need to practice boundaries, because you naturally have them as a result of needing nothing. You have great stuff in your life, so you naturally bilge out anything/any one/any behavior that sucks or makes you feel bad.
When you don't have true abundance, you sadly "need" people. As a result you will do whatever and give up whatever to get their affection. You will become anyone and sell your soul essentially to stay in good graces with them.
As a result, they like the fake you that you present, but deep down you are dying inside, because they don't like the real you.
Think of any one you know who has great abundance in any one area of life. In this area, because they have so many great options, simply don't have time for bad deals or bad people. They feel the need to, "Make something work." They have so many options, they simply pick the best ones and dismiss the bad ones the second they realize its a raw deal.
The need for abundance is important in all areas of life, but it couldn't be more true than in the arena of dating. When you don't feel like you could replace the girl you are dating, you are in deep shit.
You will allow things you would never normally allow and every time you do, you sell your soul a little more. You dig a deeper hole of neediness and dependence that can be easily exploited. You are now easily manipulated and you know you are not this person, but you feel you can't replace them, so you take it. You sacrifice you values and boundaries in exchange for the illusion of their love. Keeping them in love with the fake me is better than not having their love at all.
This is all good and well, but some day you will have to atone for this behavior. Once they discover you are so weak that there is literally nothing they could do to make you walk away, you are in serious trouble. They will lose respect and attraction for you. Worse, they will hold the strings to the puppet that you have become. They can act rude, cold, hateful, and make it look like it's your fault. You will find yourself apologizing for things that are clearly not your fault. They will become more rude and more condescending the more you try to appease.
Every once in a while you will hit a threshold where their behavior is so bad, that you will be forced to step up and have a backbone, but this insurrection will quickly be put down by their calm dismissal of your feelings and willingness to walk away. You will chase, plead, and beg for them to not leave. This will only make things worse and you fall deeper down the rabbit hole.
If, on the other hand you can hit the realization that while you do love them and would hate to walk away, you can and will walk away anytime your very clear basic boundaries and values have been compromised by their chosen actions. Not only will you walk away, but you realize you are capable of attracting people that are equally/more exciting than them and they are everywhere. This realization makes it clear that you will not accept a raw deal and will quickly punish or end the relationship if bad behavior even hints at becoming a theme.
It's not them that are rude or mean, it is you who have created this nightmare by allowing it and by allowing yourself to be disillusioned into thinking you "need" this girl or assuming she is not replaceable. This type of thinking is false and dangerous. This is a recipe for disaster, depression, and self loathing.