I Work All Day - Will My Parrotlet Be Lonely?

Will my parrotlet become lonely or stressed out, given my 8am-6pm
work schedule and the fact that I live alone? Is it ok to leave my
parrotlet alone during the day?

As I stated most people have to work all day. So long as the bird has appropriate food, a good-sized cage, lots of enrichment items and one on one time with their owners each day, they are generally pretty content. Parrotlets are not birds that require constant attention and so long as these environmental parameters are met, they generally do pretty well all day while their owners are at work. Ironically, birds that receive constant attention from their owners and are never left alone tend to have more issues with aggression, feather picking and other undesirable behaviors than birds whose owners set limits and stick to a regular schedule.