To add or not to add

Facebooks seems to be a never-ending discussion topic. In or out, add or not, privacy settings and status updates. How Facebook really works continues to be a mystery, at least for me, resulting in a scepticism and mistrust. Surely there is someone somewhere who can see absolutely everything. May be it's the same "someone" who also suggests "new friends".

How come Facebook continues to suggest that may be I should "become friends" with my ex boyfriend? Who I have no contact with whatsoever and who I only have one mutual friend with (in Facbook terms at least)? Does Facebook know something that I don't? Does he get the same nagging question (it hasn't just happened once, it's a recurring suggestion that pops up every now and then)?

I realise that my Facebook resistance makes me sound old so I may need to change my attitude and let go of the scepticism. But still not sure about "adding" the ex.