We can't keep possession because of the way we set the team up. We set ourselves to defend, and that's what we're doing. If we were a bit positive in our approach to the game as I suggested, maybe we could have kept the ball for a bit of time and wouldn't be under siege.
Think you have the cause and effect backwards here. "Be more positive" is difficult when the opposition is picking your pocket every time you go forward. Chelsea do that to teams...along with Diego Costa, it's what separates this iteration from past sides.