In winter, the relative humidity in my apartment typically drops to ~around 25%.

I've never seen ~ with percents since the percents come from real tangible insights.

It's a good thing for my towels because they can absorb more water, but it's a really badterrible thing for me anyway.

Technically correct, but this sounds more natural. Really Bad is used for unspeakable horrors, but you are clearly speaking about them so something like terrible is more natural.

My throat is constantly dry, my eyes are burning, and I feel like I'm living in a desert.

I would like to buy a humidifier to increase the relative humidity in my room at least, but a good product that can handle my room's air mass is pretty expensive.

I tried to find another solutions, like putting wet clothes or towels on the radiator or to mop the floor with a little more water, but these aren't helpful at all.

I'm tired of being a dry husk.

I can't even read more than a few pages, and my eyes turn red and start burning like hell.

It's funny because in my previous apartment, the humidity was extremely high.

It was around 75-80%, so I had to buy a dehumidifier, which was also not cheap.

So now I have an apartment with an unhealthily low level of humidity and an expensive dehumidifier, which I can't use.