Sorry to hear about your fears. It is normal to feel anxious in such circumstances. You may want to consider some of the below mentioned safety measures to feel reassured. 1. Accompanying him on the journey initially. He may feel embarrassed but it would be helpful to explain your fear and negotiate a plan. 2. Asking him to contact you by mobile phone to ensure his safety. If the above mentioned doesn't help, you might need professional help. Best wishes.