But I am the stuff of happy endings / Though mostly bluff, belief suspending / But close enough for just pretending / To care? What’s THAT supposed to mean?

The new Aimee Mann album, Mental Illness, is winning all sorts of critical acclaim. That’s great, but something about it struck me as odd. Perhaps it’s because the album is, by Mann’s admission, a concession to her own stereotype as a purveyor of slow, depressing tunes. It’s as if she figures if people are going to have this image of her, so be it.

But Mann is far more complex than that. She’s not some adult alternative whiner with an acoustic guitar, working out vengeance on all the ex-lovers and high school bullies who’ve done her wrong. Her most recent studio work is an album with Ted Leo, a worthy partner is music and on-stage comedy. (The band is called “The Both.”) She has a sense of humor — wry in many of her lyrics, downright silly in her outstanding Christmas variety shows with guest musicians and comedians.

The Christmas shows give us a very different glimpse of Mann as the guiding force in a chaotic swirl of holiday cheer, comedy and thoughtful music. A sincere Mann rendition of a Christmas carol might be followed by comedian Morgan Murphy in a skin-tight suit rapping about being the Hanukkah Fairy. John Roderick might come out and deliver a great monologue about the record industry and then launch into one of his thoughtful songs. And somewhere in the mix, Leo and Susanna Hoffs might turn Walk Like An Egyptian into a bilingual Hanukkah tune, or we may see a clip of Michael Cera refusing to be typecast in A Christmas Carol — “no fucking Tiny fucking Tim!”

So after 10 years or so of amusing variety shows, some endearing sentimental-but-not-brooding tunes and an out-and-out rock album with Ted Leo, she’s back with an album living up to some old stereotype of her?

Sounds like a terrible idea. Until, of course, you listen to it, and it’s pretty good. I’m sure it’ll grow on me even more after I see Mann and Jonathan Coulton, who guested on the album alongside her regular collaborators Paul Bryan (bass, production) and Jamie Edwards (keyboards), later this week.

But here’s what bothers me: I recall Mann’s previous down-in-the-dumps work being unfairly crapped upon by various critics. That might be a misconception on my part. Her albums all do fairly well at Metacritic. It’s just some Wikipedia editor thinks every freaking album ever released needs the viewpoint of Robert Christgau, and with apologies to his acolytes, his is not an expansive view of the world.

Mann has actually gone through several phases, and we can safely say she’s the only person alive who has recorded with Squeeze and Rush. (Hey, if Difford and Tilbrook want to borrow Geddy Lee for their next album …) I’m With Stupid, with significant Difford and Tilbrook contributions, showed some of her rock sensibilities, opening with a nice powerful guitar riff and the line “You’ve fucked it up …” Then director Paul Thomas Anderson built the film Magnolia on her music, with Save Me earning an Academy Award nomination. (And now nearly two decades of tongue-in-cheek jabs at Phil Collins, who won the award that year for something I would’ve forgotten if not for South Park.)

Christgau may disagree, but her best album is Lost in Space, which captures all of her best traits — thoughtful lyrics, memorable hooks, a few Beatle-esque flourishes and solid arrangements throughout.

The title track posits Mann in a state of disconnected ennui. She’s pretending to care, and she’s gone but she don’t know where.

If the album is entirely about addiction, as some reviews interpret it, then this song is an effective counterweight to trippy-hippie rock. (I may or may not have just watched an AXS mini-documentary on Jefferson Airplane, shaking my head throughout at how far removed they actually were from their alleged “peace and love” vibe.)

But it’s clearly not just about addiction. It’s about a hollow relationship, a common topic for Mann even as she approaches her 20th anniversary of being happily married to Michael Penn. “It split like a cell / And man cannot tell / The lie from parallel / So baby beware / I’m just pretending to care.”

I’m lost in the first verse. I have no idea about “the planets shifting, the moon erased, its features lifting the glare.” Bad trip?

In any case, the picture is painted beautifully. She’s drifting in space. It doesn’t sound like a horrible place to be, but it’s also not great. It’s not hell. It’s limbo. And detaching oneself from it sounds like a pretty good idea.

And it would fit pretty well on the setlist on the tour supporting an album with more portraits of people who’ve done (or been done) wrong. Hint hint.

And maybe make a video for it so we’re not using some random concert footage.