The Hammers boss, like thousands of supporters at Upton Park, was left understandably stunned by John Terry's last minute winner in the fourth round replay at Upton Park but insists that his players must now show their character to overcome Sam Allardyce's relegation favourites.
"I was disappointed that Chelsea didn't have to work hard for the three goals they scored," said Glenn, "but I was very pleased with our overall performance against a team who are on top form at the moment.
"It hasn't been difficult to pick the players up because I had a good 20 minutes with them in the dressing room after the game on Wednesday night and sowed the seeds of not wanting any miserable people around me the next day.
"I can't stand people feeling sorry for themselves. Be disappointed, be upset, but let's get back to work and get over it. The season is far from over. We've got an opportunity to finish in the top half of the table and it would be fantastic if we could do that. There is still a lot to play for."
Looking forward to Saturday, Glenn admits that a battle is in store for his team - and that they must rise to the occasion to ensure that our poor record away from home against the teams in the lower half of the table comes to an end.
"Bolton is the one team we haven't played yet this season. I saw them play at Tottenham on Tuesday night with a few players missing and we could be facing quite a different team on Saturday.
"Sam Allardyce has done a great job with his squad. They started the season very well and have struggled slightly in recent weeks but they are still working very hard to put things right and preserve their Premiership status.
"We have now got to concentrate on closing the gap between ourselves and the teams above us. The league is extremely tight this season, both at the top, in the middle, and at the bottom and it is important that we get a good result on Saturday to keep up our aim of finishing in the top half.
"We have got to put the game against Chelsea behind us and look forward. The game against Bolton is now the most important of the season and the players will all be eager to bounce back."
Although influential defender Tomas Repka will be missing through suspension at the Reebok Stadium, Glenn should be boosted by the return of Fredi Kanoute, who is now recovered from a slight hamstring strain.
Says Glenn: "Fredi came off against Blackburn slightly feeling his hamstring. He knows his own body and said it just tightened to leave him feeling as though it could go completely.
"We took him off as a precaution in the hope he would be fit for the Chelsea game but he didn't quite make it.
"The important thing now is that he will be fit for the trip to Bolton, which gives us a good chance of getting something out of the game."