"I want a nice guy."
"I want someone who respects me."
"You're really nice."
...
"Why are there no good guys left?"
The problem is that the guys you go for don't meet your expectations. You put the guys who meet those expectations on the back-burner since you think they'll still be around once you've run your course with those bad guys. Think again.
Here's what you need to know about them:
You're trying to fix them, but they will treat you poorly without a care in the world. On the other hand, you take advantage of the hearts of the 'good guys', the guys who treat you with the respect and care that you want. The guys who treat you poorly capture your heart and mind because you're instantly attracted to them, but they manipulate you and mess with your mind. You don't immediately see the good, but that's just fine. Those who typically treat you with that desired respect and care will be gone before you realize that the bad guys treat you like trash and you deserve better. You deserve better than the guy who manipulates you and messes with your mind.
However, you claim the good guys are too easy or too available because you want a 'challenge'. That 'challenge' is someone whom you think you can fix, so you prioritize it. OK, that's understandable, but a good guy is a challenge too. Naturally, you have expectations that you want to be met, but a good guy meets those much more easily. But it will be too late since the good guys are done waiting for you.
The guys who show you the respect and care you want are prioritizing you. They will respect you, give you gifts, lift you up, bring you on dates, show interest in you, make you a priority, be patient with you, and be there for you, just like your ideal man. But they'll walk away and stop thinking of you as a priority since you've shown them that you aren't worth their time right now.
The bad guys can never meet your expectations, no matter how much you get them to change. Once you leave a bad guy whom you've 'fixed', he'll go back to being the person he was before you met him. You want a bad guy to be someone that he is not. Saying that you want a good guy and is not the same as going for a bad guy and putting the good guy on the back-burner.
When you go for the bad guys whom you try to fix, they treat you poorly and it's harder to find where the good guys are. After long, you finally learn that a good guy is the guy you want, but it's too late because what you want now is harder to find. However, not all is lost.
You might end up feeling alone wondering where all the good guys are. You have the answers to all that wondering but you actually know where those guys are. You're just not thinking hard enough.
One thing to know is that a good guy will never tell you he's a good guy or that he's the kind of guy you need since you won't believe him. He won't be able to know what a good girl looks like because you're not making yourself available to him. But the guy who treats you with the respect and care you want will give you multiple chances that you haven't yet given him, and perhaps you may never give him.
You don't need to fix a good guy, but you can work with him to have the best relationship possible. He'll be more receptive to that challenge unlike a bad guy who is too stubborn to realize his ways are a problem for you. He isn't willing to work on the relationship since he doesn't care enough. On the other hand, the good guy has standards and is willing to change to be better. He knows how to treat you as a priority rather than an option, because he shows interest, he's there for you, and does the things you want out of your ideal man. But since you don't value him like he values you, he will stop doing that for you.
The fact of the matter is, a good guy will still be ideal for you, but he will determine that you're not worth his time and move on from you. Because you think the good guys don't exist, you fail to recognize such a guy when he appears. However, a bad guy is unable to meet your expectations. So shut those bad guys out, because the good guys who meet your expectations of the ideal man do exist.