I think my fiancy has morbid jeolusy. wht will my role to prevent it?

You can't: "morbid jealousy" at this time is a grave danger sign that you will end up an abused wife. This is the 21st century and i hope you have a choice on who you marry. I do not want you to end up with a husband who isolates, blames or abuses you "because he loves you so much." you can end up with your life ruined or dead. Please take stock of all your options now; it is not your fault.

YES/NO: First , you need to find out if your fiance has "pathological jealousy or not. Also the whole situation needs a more accurate assessment by a professional. Better if you see a professional to thoroughly evaluate the situation and determine the best course of action. But as other physicians answered, if in fact he suffers from that, then you will want to plan a safe separation. Good luck.