how to unlink facebook entirely from my iphone ,so people wont see all my info on my facebook just by entering my phone number

SOS SOS

I was playing around with my 4s and discover that I can use siri to post status for me on my Facebook,so I linked it with my iphone. And then I just realized from a friend who is not using facebook at all but just by entering my phone number which linked to my facebook and get to see the whole facebook information.

I keep my facebook pretty private which i only use it to connect with my close friends and family,I feel totally freaked out by knowing that now anyone could get to read my basic info and see what profile photo i have at the time,I dont want it at all ... I deleted the facebook account on my iphone from setting and do whatever info i found online in regars to this,but in my friends contact,he can still see everything! What can i do to make it go away?? I dont want it at all!!!

please help!!!😠