This is normal with a person (particularly male) who has been molested as a child to have a host of insecurities later on in life. Many times they feel that it was their own fault that they were molested, and/or that at some time they should have done something to stop it but didn't/couldn't.
You can try and talk to him and be supportive. You can show him that you ae able to be trusted, and that you can be counted on. Most of all, you should suggest he seek therapy. A good therapist will be able to help him work through his guilt, his memories, his insecurities and any other emotional baggage he may be carrying on his back. Please let me know if you want to talk further.
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