Chris Wood scored the only goal of the game as he profited from a Dean Henderson error when the Palace keeper allowed a shot from 25 yards to squirm past him, summing up what was another unsuccessful outing for Glasner's team.
"We are all frustrated and disappointed as always one or two situations decide the game. At the moment, it goes against us, but we have to get through it together," Glasner told Sky Sports.
"I saw the team fighting from the first to the last second, we created chances, hit the post twice. At the moment we don't score goals and we have to be honest. No goal today, no goal v Liverpool, no goal v (Manchester) United, and if you play like this it is difficult to win.
"We make one mistake and we get punished. That is the situation we are in."
Palace struck the woodwork twice and created a few other chances but most shots ended wide of goal, were blocked or too close to the keeper.
"In the final third we very often took the wrong decisions and this is through a lack of confidence," Glasner said. "Maybe you need one to hit the post and go in instead of post and out.
"Sometimes you need an easy goal but at the moment that is not arriving for us."
Winless Palace are in 18th place in the league with three points from a possible 24 and a home game against Tottenham Hotspur next up on Sunday.
"I see the players now in the dressing room and it is our job to support them to lift their heads up and stay positive, but it's not that easy," Glasner admitted.
"We have to rely on the experience of the group, as some of the players will have seen this at previous clubs, to come back and work together and go again."
