How to see the in laws less?

Is there a way I can get all of the in laws off of my fiancés di**? They are constantly bugging him, borrowing stuff from him and using him. He loves them dearly which is the issue. I do not like them but I refuse to fight with them because I don't want to hurt my fiancé. So how should I handle this situation and try to get them to back up and respect my personal space? Or do you think I should call off the wedding?
Added (1). I literally ask my fiancé everytime he gets a call/txt who it is. Not because I think hes cheating but because I think its one of his family members asking for money, or asking for him to buy them a car, or take out a mortgage for them etc… Like pretty serious stuff they expect from him.

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