Chesterfield were two minutes away from claiming a crucial win following Akwasi Asante’s cool 80th minute penalty.
But they failed to deal with a Josh Rees corner with two minutes to go as sub Adrian Clifton powerfully headed home.
“It is always disappointing when you concede late,” said Cook.
“We had the game in the palm of our hands and we buckled.
“It is very disappointing defensively to have conceded the goal in the way we did, but I couldn’t ask for any more from the players, they gave it their all to a man.
“The fans will go home a bit disappointed but a point here against a strong Borehamwood team can’t be underestimated.
“You will always get moments that present themselves and when they do you have to take them. We didn’t really have anything clearcut.
“We are disappointed but we must respect the point. The players worked hard this week on putting in a big performance for the fans.
“We never got the result that we clamoured for and which would have set us home happy but on reflection it's not a bad point.”
It leaves Chesterfield trailing County by four points and having played two games more.
They have now lost 22 points from a winning position so far this season.