How to take care of tiny brushes?

I thought you guys could help me with a brush question!

I used to buy cheapo 0/12 brushes for my fine details, since the brush tips develop bends so easily. But I decided to invest in some Princeton Mini brushes, hoping these would hold up better.

The slightly larger brushes I bought are doing well, but my 0/12 brush is struggling. How can I take care of it? I have brush conditioner, but it doesn't get rip of the bend. I think mixing my paint is contributing to this — do you guys use different brushes for mixing rather than painting? I use liquid acrylic and the larger brushes pick up so much of the paint when mixing, it's kind of a waste because I can't get the paint back onto my palette.

Any guidance? Thanks, everyone!