I think my name is one of my favourinte things about me
Kathleen is an Irish-ised version of Katlyn (or Caitlin or Katlin or whatever)
Ósuileabhainbere can be broken down in to Ó, suileabhain and Bere. The Ó literally makes the rest of my name mean Grandson-of, so originally this would have been a first name of a boy.
The second part is the 'real' part oof my name, again an Irish-ised version of Sullivan. The "bh" combination in Irish sounds like "v" (The same way "ph" sounds like "f" in English, don't you hate linguistics?).
Lastly is Bere. This is often left off of peoples names, leaving them with just Sullivan or O'Sullivan (anglisied versions), butt the Bere part (often seen as Beare) is the Clan name. O'Sullvan's have a long history and if you're intersted just google it, there are lots of accounts, but basically there are two Clans. The Moore's (meaning large or primary depending on how it is read) and the Beare's (meaning secondary).