<human>: I'm a fairly good-looking 28 years old male. 

During last years, i'm having this trouble (it's almost a curse now) where the girls that we like each other lose interest in me really quickly. This is pretty much how it goes; we like each other, start dating, and they lose interest. 

During the dating period, what happens always varies. We might have good sex, bad sex, or no sex at all. What we do with them when I date them first time also varies, since it's very obvious that I don't like doing expensive stuff once you know me, we usually go hang out and have a chat somewhere outside (pretty much just getting to know each other), have a beer maybe, it depends mostly on what kind of a girl I date really. After the first date, they usually agree on dating again once or a few more times. But it always ends up in the same way. Another common thing is they don't last more than a month, obviously.

I think this started after a "unpleasantly prolonged relationship" that has ended 2 years ago. I was never the most confident guy, but I can see that I have lost a bit more of my self-esteem after that. I was basically tolerating a girl[32 years old]  who had issues, including some serious "father issues", for 2 years (Yes I know, never again). While seriously tolerating her, I think I might have lost some of my mental balance.

I don't think if this is a coincidence, my relationships always used to last alot longer than that, I mean like, since high-school. I think it wouldn't be false to say they lasted on average, about a year or at least a couple of months.

Can you condense the text into a few key points?
<bot>: Girls I date lose interest in me really quickly and I think it started after a "not so pleasant" relationship which lasted way too much then it should have.