Alberto Gilardino scored the only goal at the San Siro as Inter lost their first home match in 2013 to slip behind in the race for Champions League qualification.
Stramaccioni believes that Inter must fight in the final 10 games to save a season that started out in promising fashion.
He told reporters at the post-match press conference: "We have lost an opportunity tonight, but there are 10 games to go and we should reserve judgment to the end of the season. It would be an unforgivable error to throw in the towel now.
"Of course we are angry and sad at the situation and at ourselves, but there is time to make up for it. We came out for the second half fortunate not to be behind. Paradoxically we did better after the break and that was when Bologna scored. It was a heavy blow.
"We reacted and went close to an equaliser, but the result is what counts. It is not a positive time for us, but I see other teams who have had problems. It is a very balanced League and apart from Juventus every team can cause each other problems."
Inter are now fifth in Serie A but switch to Europa League action in midweek against Tottenham Hotspur, who hold a 3-0 lead in the tie ahead of Thursday's second leg.