You are finding out exactly what we're talking about first-hand. Dudes be thinking we're joking or 'bitter' when we point that out, but you are experiencing what we're talking about.
Women don't appreciate what you 'do' for them. You could have been with them in their darkest hour when everyone else abandoned them and they'll still leave you. She could have been extremely obese and you were the one who sat back and gave her the chance, helped her lose weight, and she'll reward you by using her newfound looks to get with another dude.
The only thing most women care for is her 'feelings', especially in a day and age where they are told to 'follow their feelings' and to 'discover themselves' all over television and these books. More times than not, a new, 'mysterious' dude will give her feelings that you cant since familiarity diminishes feelings. Any time a woman talks about needing to discover herself or needing to take a break or some such nonsense, 8 times out of 10 she's bored and is ready for another dude if she hasn't already been dealing with him. Think about the story of Adam and Eve. Eve had access to EVERY tree except the one she was told not to eat, and yet that's the one she went for.
Honestly man, don't waste time 'getting revenge' on her. Focus that energy on improving your life. That will be the best revenge when she sees you doing better than ever. That also brings up another point. You can't save them. If a broad has a history of returning to screwed up situations, she is addicted to the drama. They'll keep the nice and stable guy around as a 'rest haven', aka a guy they can use for resources and emotional rejuvenation until they can eventually go RIGHT back to their messed up situation...
This is why I tell negroes to stop falling for that 'i can't find a decent man' rhetoric broads start to kick when they hit 30. This so called-nice dude doesn't become their type. They're essentially saying I need a provider to pay my bills and to give me emotional recuperation before I eventually go back to my bad boys.
"who can find a virtuous women for she is rarer than rubies"
there are a few women out there who will be there for you through thick and thin and we call them Mom.

, cut her off and never look back, many men sell themselves short and think "ill never get a girl like that again", or i'll be single forever, or i don't want anyone else, i'll never get her over her

