Reese McHenry and Spider Bags play the Nightlight Friday, Dec. 9, with Flesh Wounds and Boykiller. The 9:30 p.m. show costs $5.

It’s a slow Saturday afternoon inside The Cave, Chapel Hill’s oldest and most functionally named bar. A football game plays on the television screen with its sound muted. Rob Walsh is tending bar. The grizzled, tattooed bassist of Bitter Resolve talks like Jeff Bridges’ The Dude character in The Big Lebowski. But today, relaying a story about a show his old band, the Dirty Little Heaters, played in Wilmington two years ago, he’s barely able keep his feelings in check. He inches toward tears.

“It was weird; nobody thought we were the band,” he remembers, laughing. The Heaters, he says, were goofballs, a motley assortment of somewhat awkward people. “There are all these big dudes and this kind of tough guy rock scene. We were playing with Mancrusher or some shit like that. Who knows?”

But when the band stepped onstage, the tough guys suddenly started believing. Walsh pantomimes the incredulous crowd’s shocked reaction to the Heatersor, really, to his friend and bandleader, Reese McHenry, and her endlessly emotive voice.

“The moment she opened her mouth, everything changed,” he says. “All these people were like, ‘What the fuck was that?’”

During the last decade, McHenry’s throaty, Janis Joplin wail has given many doubters the same shock; she’s an enviable singer, long delivering her garage rock with a magnetic kind of gusto. Two years ago, though, a series of strokes and surgeries nearly silenced McHenry’s voice. To the delight of friends and fans like Walsh, she’s now busier than ever before.

Walsh doesn’t remember how long it’s been since he had the same reaction. It was “many beers ago,” as best as he can recall; that was 2005, McHenry corrects. He was working at The Cave then, too, hanging out in a back room as one of the night’s bands, the Dirty Little Heaters, loaded in. At that time, the Heaters were a duo, with McHenry singing and playing guitar and Melissa Thomas (of 307 Knox Records and the defunct Troika Music Festival) on the drums. McHenry doesn’t have the stereotypical chick-in-a-rock-band build; a 2008 Dirty Little Heaters’ 7″ sported the sarcastically self-aware title Fatty Don’t Feel Good. Taking one look at the pair, the impetuous rock dude wasn’t expecting much”Indigo Girls or something,” he laughs.

Instead, McHenry delivered “the most devastating voice ever,” Walsh says. “We’ve been friends ever since.”

They became bandmates, too: In 2007, Dave Perry replaced Thomas on the kit. Walsh joined on bass. Keys player Doug White joined, and in 2009, the quartet cut a 33-minute punch in the gut of hard garage-blues, called Champions of Imperfection. But something wasn’t right. McHenry was an unleashed frontwoman, or, says Walsh, “a fucking runaway truck.” The band started canceling shows simply because she wasn’t feeling well. But McHenry wouldn’t quit. Her health didn’t seem to have the same resilience as her holler. In May 2009, almost immediately after finishing the LP, McHenry hit a wall. Her heart was behaving strangely, and she didn’t have the energy to keep making music. She was diagnosed with atrial fibrillation, which she compares to her heart behaving like a jazz band that flails around without rhythm, direction or energy. She suffered several strokes. That seemingly relentless voice went quiet. McHenry was bedridden. Her friends were deeply concerned. Her future seemed bleak.

“There were months I was afraid I wasn’t going to live, much less play music,” McHenry says. “I would get this cold, terrifying fear that I was going to stroke out and die, and there was nothing I could do about it. I used to wake my husband up and say, ‘My heart’s going to stop. Don’t let my heart stop!’ He would put his hand over my heart until I fell asleep.”

McHenry is matter-of-fact about what she went through; an instinctive jokester with a contagious grin, she handles these medical problems with a survivor’s thankfulness. She’s just lucky to be alive, so she doesn’t mind telling the tales. For Walsh, on the other hand, it’s hard to talk about McHenry. It’s not about the band they’re no longer playing in together. “I was more concerned about losing my friend,” he says, turning away as his face reddens.

One of McHenry’s strokes left a dead spot in her brain. A cardiologist told her she’d probably had TIAs, or transient ischemic attacks. She didn’t know that these episodes had another namemini-strokes. It was only after two MRIs and a neurologist’s casual stroke-related questions that she realized what had happened. “‘Are you telling me your cardiologist didn’t mention you might have been experiencing TIAs?’” McHenry says, reciting his question. “I stared at him stupidly and said, ‘Are you telling me a TIA is a stroke?’ We both would have laughed if it would have been a sitcom, but as it stood, we just stared at each other for an abnormal amount of time. He whipped out the MRI and showed me where my brain exploded.”

For months, McHenry could do nothing but watch TVno playing music, no painting and not even any reading. She was in and out of hospitals, with doctors at Duke trying this beta-blocker and that fix until they realized the medicines were only exacerbating her condition.

“I had heart surgeries that would work for a month and then go back to [atrial fibrillation], which was very frustrating,” she says. Eventually she agreed to a process called atrioventricular node ablationessentially disconnecting the flow of current between the bottom and top halves of the heart to allow a pacemaker to regulate the struggling lower portion permanently.

McHenry slowly got back to work. She started writing, eventually crafting 100 songs that she planned to turn into separate studio albums without playing live. But another musician, Dan McGee of the band Spider Bags, convinced her that the best therapy for her weakened voice and decreased stamina was to get back on a stage.

“I got the feeling that, after her operation, Reese hoped everything would go right back to normal, that her energy and voice would be the same,” says McGee. “She was really hard on herself when that wasn’t the case.”

McGee describes McHenry as a perfectionist and says he reminded her she would only build back up to full strength by playing out as often as she could handle it.

“Seems to me that she had a lot of energy building up while she was sick and was just not physically able to do all the things her spirit wanted to do,” McGee says. “Now that she’s better, all that kinetic energy is being released and she’s super creative. It’s impressive.”

Not only has she been playing solo and with her new band, Lake and Hennepin, but she’s also been fronting Spider Bags alongside McGee. She’s currently making an album with Spider Bags, another with Caitlin Cary, another with Dirty Little Heaters drummer Perry and yet another with Chris Rossi of Spacelab Studio. And she’s back to painting, via her own unhindered approach of throwing paint on a canvas and then spraying it off with high-pressure water.

In spite of this, and almost against her own artistic instincts, she’s forcing herself to be careful. Walsh and McHenry are both quick to point out that Dirty Little Heaters never actually split up, for instance, but McHenry’s not quite sure if she’s ready to lead the rowdy troupe that was so demanding on her voice yet. Walsh says the Heaters might play again by the summer.

“I find I’m learning as I go,” McHenry admits. “Sometimes I don’t realize I’ve crossed the line until I’m stupid sick and pissed off, in bed.”

Back at The Cave on a sunny Saturday afternoon, Walsh is OK with taking the slow approach for the return of Dirty Little Heaters. Walsh is confident it’ll happen, and he can’t wait. Mostly, though, he’s glad to still have his friend.

“She rules, she’s awesome, she’s not going to die,” he says, smiling. “Great!”