Aha. I'm not surprised to hear about your background, Gruff, and am glad you've made the connection.
Rather than quote myself at 08:01 ('deserving' and loving well), I'm offering you a lightning summary of my experience. It's the same as many others. Having a painful childhood makes you "capable". It's a triumph to survive; to build ambitions; to create a successful life in spite of all that. Most of us overdo it, in fact! This makes you feel brave, strong and proud ... and as though you can handle anything. Well, maybe you can. Stately Homers can certainly handle more than most. We - and you - have a lot to be proud of.
But there's a difference between knowing you can handle the shit life throws, and feeling you have to keep proving it. The way to keep proving it is to seek out shit to handle, isn't it? I chose men with evident needs - inadequate, faulty men basically. I was hugely attracted by the feeling I could handle them and I could fill up the yawning gaps in their personalities. Show me a decent, sane, balanced man and I'd go "Not my type."
Overachiever that I was, I made a very attractive prospect for those faulty men. When they realised I'd put up with any old crap and even try to 'help', they must have thought all their Christmases had come at once. Did they lavish me with loving care, respect and delightfulness in return? Of course not! They treated me with the contempt I was used to. They were abusive in (slightly) different ways from what I'd known as a child - of course, abuse feels different to a dependent child. The urge to fix it is the same, though.
It's all a bit much to take on board at once, and I'm sorry my summary hasn't been that quick after all! You're making all the right connections now, though :) As long as you don't get yourself too locked into your current relationship, I'm pretty confident you'll figure out what you're really worth and find men who agree with you 
PS: No wonder your dad was less than decisive on advising you to quit 'helping' a faulty partner ... he didn't, either, did he?