If we take a more general, social look at relationships, then it'll probably look like there are more bastards/bitches around than ever before. The divorce rate is high, people treat relationships as disposable and are always looking to 'trade up' because we're taught to aspire for better and to want more. The moment things aren't going well, there's talk of breaking up...or there's cheating.
I was with my first partner for ages...and a lot of my friends would moan that he was too nice, too 'fatherly' and not enough of a go-getter. Meanwhile, they were dating asshole after asshole ..it was their choice, though. It wasn't that they couldn't find nicer guys...it's that something about the arrogance/cockiness appealed to them. So, it can also come down to who you attract and what you're attracted to.