Staying in a hand for the sake of staying in a hand is not only bad for your wallet, it can be incredibly frustrating.
You can see that the only way for you to win is to bluff, but bluffing is a tricky thing to master. It is an even harder thing to do when you can see your chips pouring into the centre of the table over a hand you are not confident in.
Unless you are at least 70% sure the other player is going to lose, rather fold. There is no shame in having a few extra chips to use in the next round. Who knows, it could be the round that you get That Card, and need those extra few chips to show it.
And if not, at least you have some capital to try again.