Vanderpump Villa star Grace Cottrell was in it for the long haul when it came to her time working as a housekeeper at Chateau Rosabelle. “Of course I had moments where I was like, ‘Aw, man, this is exhausting. I don’t know if I can do this,'” she reveals in an exclusive interview with OK!. “But I never had a moment where I said to Lisa [Vanderpump], ‘I need to leave.'” “I knew in the back of my mind, like, this such a once in a lifetime opportunity,” she explains. “Even in the hard moments, I gotta power through because I don’t want to pass this up.” Throughout her time working at the sprawlin…