How do I stop Minecraft from turning pink while I'm playing??

I haven't had this issue until recently. I used to be able to use shaders and resource packs and have like 100+ mods without any issue.

Now, after a while, all my textures will turn pink and I have to reload the entire game. And it just keeps happening over and over. It's so stupid!

I've tried every combination of settings and optimization mods but unless I turn off shaders and resource packs completely, I get pink textures. Which sucks because default Minecraft is so UGLY.

Any Minecrafy pros out there know what I can do to keep my shaders and resource packs without falling victim to the pink?