Lance Bass Is 'So Proud' of Jamie-Lynn Sigler for Going Public with MS Battle

Lance Bassofficiated her weekend wedding and helped her celebrate her last night as a single lady with a Vegas bachelorette party. Now, the ‘NSYNC boy-bander is supporting pal Jamie-Lynn Sigler during a more trying time after she revealed her health secret: She was diagnosed with multiple sclerosis 15 years ago.

The Sopranos star went public with her battle in an exclusive interview with PEOPLE for this week’s issue.

“I can’t walk for a long period of time without resting. I cannot run. No superhero roles for me,” Sigler, 34, said with a laugh. “Stairs? I can do them but they’re not the easiest. When I walk, I have to think about every single step, which is annoying and frustrating.”

• For more of Sigler’s revealing interview, including exclusive photographs from her wedding album, pick up this week’s issue of PEOPLE on newsstands Friday

But the newlywed mom of one is staying positive, telling PEOPLE, “Things are manageable now. It takes a fighting attitude to deal with all this. This disease can absolutely take over your life if you let it.”

On Wednesday, Bass, 26, shared his friend’s Instagram announcing the news.

“So so proud of my girl!!” he captioned a black-and-white snapshot of the actress playing baseball with her husband Cutter Dykstra and their 2-year-old son Beau.

• For more on living with MS and to contribute to the fight against the disease, visit The National Multiple Sclerosis Society

Bass’ husband Michael Turchin also re-posted the photo with the caption, “I couldn’t be more proud of my friend. She inspires me every day.”

And other celebrities like Haylie Duff are using social media to reach out to Sigler.

“So proud of @JamieLSigler shes brave & a truly beautiful heart,” she tweeted. “She’s setting such a fab example 4 girls everywhere.”