There is no question that this team is beat up at the moment, with Wilfork and Mayo being down for the count.
This team is by no means sunk, however. Many key pieces are slated to return this season.
On offense, chemistry is getting better each and every week between Brady and the rookie WRs. Gronkowski should be back soon, and Vereen will return in week 11. If the offensive line can improve even a little in pass protection then this offense could explode. It won't be 07 Patriots or 13 Broncos level of elite, but it will be a very respectable offense, one that should be able to carry the defense in some games.
On defense, the big players missing (that are not on IR) are Kelly and Talib. With the next 3 games being @ Jets, vs Dolphins, vs Steelers, and then the bye week, I think the Patriots can afford to sit them and allow a suitable recovery time. Speculation on my part, but Kelly probably has a knee sprain, and Talib has a minor hip flexor. 3 games plus the bye week is a month of rest; that should be ample time. Additionally, Armond Armstead could come off the NFI list at any point in these next few weeks, and he could certainly be an upgrade over the likes of Forston, Vellano, Jones, Neblett.
Until then, the defense is still good enough to get by. Run defense is not at the level this team usually is at, but the secondary is holding up it's end, and will continue to do so even without Talib.