river decisions

[groth911t]

I'm pretty new to PLO and having a lot of trouble on the river. Two examples:

1/2 PLO, I raise with aaj7 doublesuited on the button, get 5 callers, the flop comes j103 rainbow. I check behind thinking that someone had to hit this flop. Turn card is a 2 giving me the nut flush draw, i call a half pot bet, the river is another 2 for jt322 He bets out the pot, and i make a crying call.

Another hand: 1/2 PLO on the turn I have the nut straight with a small spade redraw, the river the spade hits, i'm oop and we both have about a pot sized stack. I checked and called, because he had raised me on the flop and the spaded got there runner runner so I thought a big flush was less likely.

I could post a lot of hands like this where I folded as well. Am I better off just folding non-nut hands on the river to big bets? It seems like I'll just get eaten alive if I do this, so I'm looking for a rule of thumb on these river decisions. Any advice would be appreciated.