Facebook and Bullsh*t

Is there a nice way of denying someone on Facebook? Someone I know has one and I know soon I am going to be receiving a friend request, but I do not want to accept it. I cannot decline this request so I guess I have to figure out how to make their access to my information on a limited basis. There is too much drama on Facebook. Exes harassing their exes; current spouses, boyfriends and girlfriends harassing their other's exes. It is immature and stupid. I am friends with one of my exes and his girlfriend has a huge problem with it. I have told her numerous times, I DO NOT WANT HIM, but he has cheated on her before with lots of girls so I get it. The two times we did hang out years ago when they were broken up she knew about. 'Course he did not tell her, she emailed and asked me. I told her. I was not hiding anything. Last time he told me they were going to try and get back together again, I wished him luck. I told him to stop talking to other bitches. Have not talked to him since. I hate when people try and hide something from their SO on Facebook, I have nothing to hide from my husband. And if he thought I did, he knows my log in information.