If a cat scratches a dog’s nose and the dog then later runs from a different cat, well that’s just animals with instincts. However, you must remember that humans have free will and also that every human is an individual. If one girl cheats on you then that doesn’t mean that you should never again try to have a relationship with any girls who have a common characteristic with that girl, eg, same race, age, hair color etc. But then again, sometimes it only makes sense to make assumptions, and it’s important for your self preservation. Like if one blind truck driver almost runs you over, then it would make sense to avoid other blind truck drivers in future.
Judgment is mainly a problem when it causes you to be less charitable or whatever towards another person when they have done nothing to deserve this. But generally people will be understanding if you’re not very trusting because of past experiences, so long as you sort of explain yourself so that they don’t think that you’re just being unkind for the sake of being unkind. For example, once someone invited me to a protestant bible study group. I explained to them about how I’d been in one before and the people just tried to convert me and it drove me nuts, so I didn’t want to join protestant bible studies anymore. They were understanding about it and didn’t get mad or accuse me of being judgmental.