This is like fourth time I am having same problem. I go out with a girl on first date- we enjoy ourselves, go on second date-have more fun, then go on third... she likes me and I like her. Meanwhile, we kiss each other and express that we are having great time together. Then suddenly one fine day, I stop hearing back from her. Why?

I am 5-8, well athletic, handsome, working on my higher education, earn enough, respect girls, look into her eyes while talking, treat her like a princess when she is around, pay high quality of attention; but its still the same story. Why?

Contrary to this, all my friends who treat their girls like trash always have girls. Is it like girls doesn't like nice and good guys anymore? Doesn't girl like well established, well futured, smart, handsome, ground-to-earth, hard-working and non-manipulative guys anymore? I mean what's the deal?

You've probably heard this before, and don't want to hear it again, but it sounds like you just need to find the right girl. Eventually, you will find someone who likes your traits, and doesn't want a 'bad boy.' How old are you? In my experience, girls that like 'bad boys' tend to change their opinion once they get a little older. It's the adventurous people who tend to get married right out of high school, and the humble and more responsible people who get married in their mid 20s, in my experience (What I've seen from my friends and family).

Just hold out, you'll meet a good one. In the meantime, the others will at least help you decide what you want in a girl, so you'll be able to recognize the right one when you meet her.

I don't think its about the RIght gal or wrong gal. There is a saying that has always been true " if you do the same thing, you get the same result". So I can't tell what was wrong since I don't know the conversation or the gesture or the expression between u guys. But it's the signal in which something is not OK, and you need to change in some way.
4 times doesn't seem like a coincident anymore.
So don't seek any theory called "ok, just means i didnt find the right person". That's on films!
1st u should watch the "trash guys", not to apply it to you, but see how it works. 2ndly, let me ask you: have you been so serious about something towards them (like to talk much about future or something)? Think about it!