Just Cannot get out of a bad relationship? Sounds familiar?

I've seen people get divorce, cheated husband/wife, people lying, people stealing. My trust in humanity is considered very little now, and that includes my trust in my significant other.
Does it sound familiar to you: you know you've been lied to, you have all the evidence, all the rational explanations. You have all the good reason to get out of a very bad relationship.
Yet, for some reason, you just can't.
Because you're afraid to be alone.
Because you have invested too much in this relationship: emotionally and financially. Because you're in too deep to get out.
Because the idea of starting over scares the crap out of you.
Because you're afraid you wouldn't find anyone else.
Because you don't have the time and energy look for someone else.
Because [insert your excuse here]

Do you have a similar story? I'm not sure I'm asking for solutions or advice here. But how about trying telling your story and how you handled it, that would probably give some insights.

Here's a short version of my story: I know that my partner really lied to my face. Well, I confronted before, more than once, each time a different result happened; there was time we fought like hell, there was time there was just the 'brushing-it-off' move, there was time there was lots of blaming and pointing finger, there was time there was counter-attack (tricky move and vicious one), there was time there was regrets and apologies.
But bottom line is, there was deceit and deception.
And I can't get out of this relationship. There were so many breakups. But we were weak, and we got back together after all the breakups. Maybe just so that there will be another breakup :scratchhead:
Where do I find the strength to handle this?

What is your story?