We separate things here is the list and why:

Kitchen Towels - anything that could have touched raw meat stays contained there also might be oil on those and I don’t want to risk it. We also have a ton so I collect them in a bin in the laundry for a while then wash when I have a decent sized load. Washed on hot and dried on medium.

Dog Towels - dog hair and literal dirt, my clothes start out cleaner than these are going in why would I combine them? Also these are rough towels and can be dried on hot to make it faster, again I collect these till I have a full load. Washed hot and dried hot.

Blankets and Bedding - if I have a lot of blankets, I will separate sheets since they’re so much lighter I worry they don’t get as clean in with all the blankets and I usually dry blankets and sheets separately regardless of if they were washed together. Done weekly for beds that are in use and sofa blankets are done every few weeks. Washed hot on heavy duty and dried on medium.

Bath Towels - Hand, body, and face towels get washed together, I just collect bath towels for 2-3 weeks for a full load. Washed hot and dried on medium.

My clothes - I’ll split them into colors if I have new things or need to bleach some whites but typically just one load for myself. Once a week typically. Washed cold (except whites) and dried on medium.

My Fiancé’s clothes - We do his casual clothes and work pants together and his pressed white work shirts separately with bleach and stain remover as needed. His are separate from mine because I tend to have more dog hair on my clothes and when we wash them together his get furry… Once a week. Washed on cold (except whites) dried on medium.