How to be actually happy during internship

I have noticed that I feel anxious and sad on most days of my internship - like 90% of the time I'm feeling low.

Several factors are contributing to this:

1. the insane workload and lack of personal time/sleep is one.

2. Second is the anxiety regarding what the next day will bring, especially on the day before I start with a new department, since I don't know who the residents I'll be working with will be, if they're going to be toxic, and also because I don't know the skills pertaining to that department.

3. I don't get along with my unitmates. I'm so jealous of people who have found their best friends in their unitmates; it makes a world of difference if going to work means you'll be spending time with people you actually like. I have a boyfriend and some good friends but they're all in different departments and I hardly get to hang out with my friends because of the busy schedule and we're all lazy people who want to do nothing but sleep after a long day of work.

4. I'm not able to visit my family because of the hectic schedule, so that's adding to my feeling of loneliness.

5. Anxiety regarding the future. I can't imagine working even more than I do now, but that seems to be what's lying ahead for me.

6. Fear of my co-interns dumping work on me

The only thing I have found that lifts my mood even slightly is watching series. It helps me forget my problems at least for a while. I also feel better when hanging out with my boyfriend but we haven't gone anyplace more than a kilometre away from the campus in the past 4 months because of insane work hours.

Does anyone have any advice on how to feel better in general? I'm tired of being low all the time.