I know I'm coming late to this discussion (like nearly three weeks), but for some reason I just remembered reading the thread and some thoughts popped into my head. And those thoughts are (bated breath here):

I'd like to say that if I wasn't already married, I wouldn't go looking for a relationship just to feel complete, that I'd want to work on myself for a while and THEN go out and look for somebody to whom to present the new, improved me. But, probably the better answer is, yes, definitely work on self-improvement, but if someone comes along who you think you have half a shot at, don't dismiss the opportunity because you don't feel 100% ready to take advantage of it.

Like you, Sad, I have run from relationships or potential relationships that I thought could have gone somewhere because I didn't feel like I was worth it. Hell, my wife would tell you I probably tried to break up with her half-a-dozen times when we first started going out. I know it doesn't seem possible now, but maybe try to imagine the possibility that things could go well for you, romantically and otherwise.

So my short answer to the overall thread would be, I wouldn't go seeking validation, but I wouldn't look askance at it if it came along, either.