At first I thought this is a trust issue, because you said it is a trust issue. I was planning to tell you that you can trust people to be themselves. Your expectation of betrayal can actually make it more likely to happen, because it drives off people who are mostly honest. It is just the same way with people who are angry all the time in that they are very good at finding reasons to feel angry. Things just seem to happen that way. Your expectations act like a filter on your experiences, and from what it sounds like, you are filtering for betrayal.

Except now I'm wondering ... is it possible that you are actually asking about abandonment?