The Pittsburgh Steelers are like that moody friend that everyone has.

One day, they are happy and cheerful. The next, they are surly and dour.

Forrest Gump would compare the Steelers to a box of chocolates.

You never know what you are going to get.

Pittsburgh has been very good (vs. Carolina, Indianapolis and second Baltimore game), bad (vs. Jacksonville, Tennessee, Houston) and downright ugly (in the second Cleveland game, vs. Tampa Bay, N.Y. Jets and New Orleans)

Perhaps no Steelers team in history has driven its fans as batty as this one.

Frustrating. Like having a root canal without novocain. Like being forced to watch Johnny Depp’s cringe-worthy “The Lone Ranger” movie once a week.

That’s how I’ve heard the experience of watching the Steelers on Sunday (and sometimes Mondays and Thursdays) described.

It’s a bit entertaining, though, sort of like seeing what the big prize is behind the curtain on “The Price is Right.”

Sometimes it’s a sports car. Other times, it’s an overpriced pot and pan set.

What makes it so infuriating, I think, is there is talent there to go deep into the playoffs.

Quarterback Ben Roethlisberger is arguably having the best season of his career. He has an outside shot at passing for 5,000 yards and 40 touchdowns this year.

Antonio Brown has emerged as one of the top wide receivers in the game, and Le’Veon Bell has become one of the most versatile threats at running back in the league.

And then there are the Grand-Canyon-like holes on the roster.

The defense is a shell of the unit it once was. Teams can run on the Steelers. Teams can also pass on the Steelers. The talent level on that side of the ball is nowhere near the same as on offense.

Pittsburgh no longer has a steel curtain. It has something more like a cheep, plastic shower curtain.

Still, the offense is good enough to keep the team in games.

As long as the offensive line plays well, that is.

In many ways, the O-line is a microcosm of the Steelers’ season. When it plays well, the team plays well. When it struggles, the team struggles.

If the offensive line continues to have games where it moves and protects Roethlisberger like a bunch of sloths, it won’t matter.

The Steelers will lose. And fans will be pulling clumps of hair out of their heads.

As it sits now, the Steelers are 7-5 — along with seemingly everyone else in the AFC.

It’s now a four-week season. Looking at the schedule, I can see the Steelers emerging as an 11-5 team.

I can also see them as a 7-9 team.

Should the Steelers miss the playoffs, they have only themselves to blame.

And maybe the Tampa Bay Buccaneers.

Mike Kilroy is a staff writer for the Butler Eagle.