Many times, there are people who tend to be a little sensitive, irritable and I would say that they are even complexed.
These people, after they usually have this type of inconvenience or suspicion, tend to feel bad about themselves and to hold a grudge against the person who has made them feel bad.
Many of these people tend to fall into depressions and are isolating themselves from their environment and, as you say, from the opportunities that may arise.
For that kind of people, we should try to support them, help them and make them understand that they must control the impulses and be a little less passionate about any situation of this type that comes before them.
Regards....