My friend, who was male, asked what would make her say such a thing. To which she responded, "I've been married 7 times and they were all alcoholics and assholes so all men are alcoholics and assholes."
In the 12 step programs they often make reference to having a broken picker. That is - the individual's ability to pick healthy friends and partners is impaired. There are many ways this can happen. Our parents may have modeled an unhealthy relationship for us as we grew up. Or a particular type of person may provide a little danger and excitement to what we consider a boring life. There are countless reasons but one conclusion: Even in a large group of people we will consistently pick out that one person who matches our preferences, even when these preferences aren't in our best interest.
Over time I've come to the conclusion that we can never turn that part of ourselves off. There are certain qualities we look for in others and those seem to remain with us. What we can do is to change the person we bring into the relationship. If we are healthy, if we communicate in an honest and direct manner, if we have firm boundaries then the people who stick around will be those who want those qualities in a relationship. It doesn't mean that either of us are perfect, only that we are bringing a desire for health into the equation.
Happy July 4th!
John