Somebody who has endured betrayal, and is still affected by it, is not going to operate optimally and assimilate seamlessly into dynamics. They will be reluctant and rightly so.
This is something that, first of all, you shouldn’t take personally. It does offend be seen as untrustworthy, whether you are or not, and it can test your patience to be tested for reliability, whether you’ve shown it or not. But you must understand and keep in mind that it is not about you. It is about them and what they went through that they still carry.
If you have the option, give it time and let it be. Some reassurance sometimes helps, but other times makes it worse (taken as smooth-talking that is deceiving, leading further into a scam). Do not pressure into being relied upon.
There are indeed cases when you can slowly and gradually lead another into trusting again, demonstrating that there is no or little danger into doing so, but it has its time and place. And again, shouldn’t be rushed.
It could be so that the best you can do is suggest and encourage to work it through with a therapist so that they can tackle each and every one of their fears and prepare for the probability of them, becoming more able to face and overcome whatever happens rather than continuing to withdraw from life and its uncertainty.
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