Happy could be showing signs of passive dominance, but mostly it sounds like extreme softness. A lot of NILIF and Obedience work every day could give her more confidence and discipline. Gonzo is very soft too, he would totally go limp if I tried to pick him up when he didn't want to do something, and cower and everything. Now, he's much more confident.... Just remember to be patient, BC's sense when you're getting frustrated and mostly they just want to do what you want them to. Take it very, very slow. If she seems like she's shutting down, give her some good treats and go through a few tricks she knows. I sometimes put Gonzo on a long down-stay to just chill for a while, and it always helps. He gets very frustrated when we're playing frisbeee and he isn't catching it because of the wind or I'm throwing crappy or whatever... a break always helps

Always remember to be as positive and happy as possible, tell her she's a good girl often and give her treats and praise. Make it very fun and exciting and she'll learn to love whatever you want to teach her.