Dude, it's not a matter of strength, it's self-preservation. If you're staying, it's because on some level you believe what she says about you. You are letting her tell you how to feel about yourself, and about the marriage. If your counselor isn't telling you that, then you need a new counselor! You're setting a terrible example for your kids, too. Grow a backbone and stand up for yourself, and show your kids how a real man deals with abusive situations. You're too worried about how she'll react...I got news for you, YOU ALREADY KNOW how she'll react! So what? If she wants to make herself miserable, fine! Take away the supports that allow her to get away with it, and you'll be surprised how quickly she'll change her tune. You are enabling her, my friend!
..Can't take the plunge...? What are you afraid of? Being alone? In reality, you already are! Being alone as opposed to being in that kind of marriage is much preferable! I have a motto that has helped me a lot: I'd rather be in a relationship than be alone, but I'd rather be alone than be in a bad relationship. What you have described your home-life as being like is a classic "bad relationship", and you need to get out of it, for your own sake. It's destroying you slowly. Listen to yourself! You're not acting like a man, you're acting like a whipped puppy!