The hosts deservedly went in front in the 24th minute courtesy of a goal from Garry Thompson before substitute Alan Connell won the game with a smart goal four minutes from time.
Stanley, without a win in seven matches, had equalised in the 79th minute courtesy of Rommy Boco, despite going down to 10 men when Winnard was sent off for a second bookable offence following a foul on substitute striker Nahki Wells.
Richardson said: "The linesman sent him off for handball, but his hands were by his side. This defeat is really difficult to take, I really felt for the lads. I am proud of them. They gave me everything, but some of the decisions by the officials I question.
"We came with a game plan to win the game. First we wanted to contain them and, other than one lapse of concentration in the first half that led to their goal, we did exactly what we wanted to do.
"In the second half we played some great football and the lads worked really hard and deserved the equaliser. If we had had 11 players on the field I felt we could have won the game."