The reason you're having a hard time is because these are player dependent spots. If you don't have a HUD then you will have to be very observant of your game to play these properly. Depending on my opponents stats my actions with these hands on the flop would vary greatly.
I think in the first spot you have to jam or fold, and pretty much always fold. If its down to HU by the time its your action then jam becomes a possibility depending on the opponent, but probably not. It sucks, it happens, sometimes you have to eat it.
The second one is trickier. Unless you have a compelling reason not to I think you have to cbet that flop. If the oppoenent is a super cbet calling station then maybe make it a delay cbet, so they think you were hoping to trap some value out of them by making them try to steal the pot when you checked the flop. Another trick here I love is to make a bet that begs for a call. Something just big enough to look like you are trying to build a pot, but small enough to not scare people away. Since this is a scare board, that is terrifying to an opponent who is paying any attention at all, or they are going to make a move over your top with a hand that has you beat anyway, and it didn't cost you as much as it otherwise would have.
The sad thing here is all you'll ever do is make weaker hands fold and pay better hands. With the possible exception of making some sort of k fold in the second scenario. Sometimes that's all you can do though, I'd rather make a small risk to snag the pot for myself than either call off money hoping to win a hand I have no hope in or give away my pot that was for the taking if I'd sacked up.