My yahoo was my fb email,butthen became mygmail,whats happened?

okay in 2008-09,my awesome sister did me a pretty solid favor and explained and said she was going to help me create and build my facebook account. in order to do that it requires a email account.weallready had a aol screen name,so since hers was yahoo then so was mine.okay great perfect whatever,okay.now i get around woman who is all about this google domain.aint no problem,i like it myself honestly.so googe is cool and if you want to cross over your email from whatever name it is,you can keep your own screen name and still receieve all gmail benefits as well as the comfortasto have it remain your address for you on facebook.right.right.ok,now i was just locked away gone for three years.my exdemolishedmy fb account,but when i got on togoogle its tellin me that my screen name is not a namthat the names that may have used to be upon it are not no longer,neitherare the secondary back up information in case smthing wastp happen.but i found my fb page on fbafter enough endless failures. no ive gotten onto google and gottten as far actually not needing to actually know my my password or domain address.but when i putthe informatio of my name in a variety of ways along with the back ups name,nuber,and email,imtold its not a truth, so help me please on what i need toactually do so that ican do that ahead of time my own self. because i really really wouldlike to have myp everutno sam e eail addressback so i can reactivate my old but same, fb andhopefully not have to put much effortinto my freindslist,thank you.