Quick questions (TBC)

Hello everyone. I’m 21 years old now, but I dealt with pulmonary tuberculosis back when I was in the sixth grade—so we’re looking at roughly seven or eight years ago, if my math serves me right.
I spent just under two months in the hospital, followed by another four months of home treatment; I actually kept going to school, though I had to chug about fifteen different pills every single day, which was quite the ordeal.
About six months after finishing the regimen, I went in for a follow-up. They did the chest X-rays, blood work, the whole nine yards, and everything came back clear. The doctor essentially told me I was a clean slate and that I didn't need to bother with any more checkups.
So, I’ve lived my life under the assumption that TB is a thing you get over and move past, but today, some doctor—or perhaps just a med student in his final year—told me that TB isn't actually "curable." He claimed it can be treated, sure, but that it lingers forever. Now I’m sitting here wondering if I should seek out a real professional to settle this, or if this guy was simply messing with me because he somehow suspected I had been sick before, even though I never mentioned it.

I also have another question regarding what I've gathered over the years: is it true that once you've fought off TB, you're largely immune to catching it again? My understanding was that the body retains some kind of cellular memory or residual protection from the initial battle that keeps you safe. I’d appreciate an expert opinion on that.

In the meantime, I try to stay cautious. I watch my diet, avoid greasy foods, make sure I don't let my feet get soaked, and try to stay dry and avoid excessive sweating. Am I just being overly neurotic about these things, or is there actual substance to these precautions?

Alright, here’s the breakdown on most of those questions you asked:
The primary infection kicks off right after someone breathes in the TB bacteria. Once those little guys hit the lung alveoli, the body’s defense squad—specifically the macrophages and lymphocytes—gets to work attacking them. This triggers a very specific immune response designed to kill the bacteria, which ends up turning those infected macrophages into these tiny, hard, grayish nodules called tubercles. Inside these tubercles, the TB bacteria can actually hang out and persist within the macrophages, though their ability to multiply and spread is pretty much throttered at that point. Most people who get infected the first time end up clearing it spontaneously; the tubercles just calcify, and the infection shifts into a latent stage. That latent infection can stick around for your entire life without ever actually turning into full-blown disease. At this stage, a positive tuberculin skin test is basically the only way we know the infection is there.

Now, if the body's defenses are compromised—maybe due to old age, living with HIV, malnutrition, or just other health struggles—those bacilli can break out of the tubercles in the alveoli and trigger active disease...

People dealing with a latent TB infection
don't show any symptoms
aren't contagious to anyone else
usually test positive on a PPD skin test
but they could develop active TB later on in life