Not sure if I am schizoid, never been diagnosed or anything but definitely have many of the traits.
Anyhoo, I think the longest I was without any human contact was about two weeks. I didn't leave my apartment except to pick up the mail. That was after college and I didn't live around family. I took two weeks of vacation and just stayed in my apartment reading, writing, watching TV, etc. I had a couple conversations with my mom on the phone which was mostly her talking and me pretending to listen

I can't get away with not talking to my mom, at least, once a week or she will send the search parties after me

I did not feel any problem spending all that time alone. If I had felt lonely or bad about it, I would have left the apartment. I didn't even go to the grocery. I had enough food to last that entire time.
Now, I live closer to family as they have all moved to the town I live in

My brother went to college here and stayed, my sis moved here for medical school and stayed, and my mom and step-dad moved here because that's where the kids were. I have to see my mom about once a week. I usually stop by her place after work once maybe twice a week. It's a free, home-cooked meal so why not. I see my sister and brother much less. Maybe once or twice a month even though they live close. I interact with people at work. I work three 12 hour shifts so have fours days off each week. I usually spend these days alone and don't have any issues being by myself.
Yes, I do have two cats and I like spoiling them, but I don't NEED pets. After my last cat died, I didn't have a cat for about three to four years and it did not cause me to change my routine so it's not like having a cat 'replaces' my need for human interaction...else I would have spent more time with people during those three to four years which did not happen. I just don't have a need for human interaction. My cats are not a human replacement. I have them because I like cats. I have liked cats since I was a young child. A dog is too needy for my liking. My male cat is fairly needy for a cat but no where near as needy as a dog. I like dogs too but don't think I would like to own one because they would need too much of my time and demand affection all the time. My cats love affection and to be held but they also know when to leave me alone. I don't think a dog would respect my 'me time' like my cats do

So I don't NEED to own a cat, I just LIKE to own a cat.