Guys are supposed to be happy with "she's with you now" and "she chose you now" and "she wants only you now". Aren't guys allowed to evaluate a girl before committing? Aren't we allowed to be skeptical of a girl who overlooked you and be skeptical of a girl who had a bad past? A bad past can include dating a guy that used you for sex.
Here is the thing: you can judge anyone for anything, YOU are the only one who risks losing out on somebody who made bad choices in the past as the person they once were and not the potentially amazing person they are in the present. That is the point people are trying to make. People can change, in fact it is inevitable that we do. If you judge people on all of their mistakes you'll overlook their successes and their potential.
Mind you considering trends is one thing, but ignoring all else for what they did once... it's tricky business.
Do you suffer from Mongoloidism? Keep it up and you'll end up marrying a seemingly nice girl who'll wait til tou've been married for two years, and then begin telling you the intimate details of each of the1,200 men she slept with while she was a hooker.
Yes, but thats your job to do before you jump into a relationship, you can't expect people to sympathize with you, when you know about her past and then become insecure during it due to it. Everyone should be aware of who they date, and in order to do that is getting to know them, thats why jumping into a relationship at full force without knowing them is not really the best decision.