In one sense, you're being way too hard on yourself and in another, not hard enough. If you feel like you've blown your life at age 23, I don't even know what to respond to that! In the US right now, people are adopting all sorts of alternatives to the traditional "go to college at 18 and graduate at 22". Stop comparing yourself to others, esp when you're in the majority nationwide.
Where you might be too easy on yourself is still living at home. At 23, many people are still doing this to finish up education, but that's because it works for them. Their parents are supportive, they have the freedom they want, etc. You don't have this, and I have a feeling this is a bigger problem than you realize.
If I were you, I'd be checking the going rate for rooms in a group house and then trying to make it happen. Regardless of anything else, 23 should be a fun age as you start becoming an independent adult. Then figure out how to make it happen. There's flexibility here, and you may have to sacrifice some things, work 2 jobs, or even delay that degree a bit. But you'll be a happier person. I can't imagine living with a dad who thinks you're a screw up.