At present level of canon (December 2015), nothing definitive is known about Rey's parents. There are several canon hints (which may or may not pan out to be misleading vs true); and even more fan theories. None of them have any definitive canon confirmation, and likely won't till at least Episode VIII
Where we find out that Luke and Leia are Rey's parents, tapping into Game of Thrones fandom, tying up unresolved storylines from Episides IV and V, and neatly uniting all the best fan theories. JUST KIDDING!
Other theories include:
* Luke (based on anvil-strength hints in TFA) and unknown woman (presumably, CORE world resident based on Rey having British accent and a theory that in almost all roles, that maps to Core - vs American accent for Outer Rim);
* Han and Leia
* Han and unknown woman
* The Force (the way Anakin had no father, except NO MIDICHLORIANS!)
* Some other unrelated people
Specifically to address the rumor you alluded to, it was later updated and confirmed false by the same person who originally started it. Kylo says "cursed", not "cousin" in the game.