2 10+1 stars rebuy hands

[elcheapo]

1. Blinds 400-800 w/50 ante. You (12K) raise to 2400 in EP w/ JJ and loose passive in mp thinks and goes all in. This is a must call with 500 of 1100 left or do I have enough chips to fold in this marginal situation.
2. Blinds 75/150- Different loose passive limps utg and you raise to 750 (10k stacks each) w/ AA. Flop comes 109s9s check,check. 10 on the turn and it goes check check. A five on the river and he pushes allin into me. I know I screwed up by not betting this reasonable dangerous flop but this a fold if you haven't seen the opponent overbet before. I thought it could be in his opinion another ace high pushing me off the hand or maybe jacks or queens trapping my "worse" two pair. Lets say I bet the flop, get called, check the turn, then fold to the river bet. I call a checkraise allin in an instant but I just have a hard time believing every time it takes 2-4 cards to beat me and they always do have them.