The Shrimps, safe in mid-table, are without a win in 12 league games against Stanley after goals from Peter Murphy and Padraig Amond on Friday night.
"It's really frustrating," said Morecambe manager Bentley. "We still have plenty to play for as we got 56 points last season and we have 55 at the moment and want to beat that.
"We want to finish the season on a high but I can have no complaints against Accrington. They deserved the win.
"The first goal was always going to be vital and they got it.
"It put a spring in their step, they got the crowd behind them and we wobbled and couldn't react to the goal.
"I am not happy with either goal, the second especially was shocking. It's three massive points for them but it's not acceptable from us."