Bills KNEW what was coming, many times the Pats only had 1 WR on the field & he was lined up tight so guess what comes next? You get massive double teams, small D linemen getting over whelmed, you didn't even have to play the Pats honestly regarding run or pass. The formation says "we're going to run, try & stop us" and all the Bills could say was "Huh? pardon me, could you repeat that?" as they got steamrolled again and again.
Bills run defense stopped them many times but could not stop them every time, so completely embarrassed by the way they get punched in the mouth over and over again by physical teams and they have no answer, no response.
As far as the offense goes, games on the line and they have 1st and goal at the Pats 6 and they proceed to move backwards. Playing outside in the weather that Western NY gets demands a functional efficient running game and all the Bills have is an O line that gets beaten off the snap, RB's that run indecisively so the Bills make themselves one dimensional and easier to defend. Devin Singletary (nickname Motor .... HUH?) who goes down at 1st contact, has little speed and almost non-existant shake 'n bake moves, does not run with power & authority so why is he on the team?