My mother is such an unhappy person. How do I get her to realize it’s not punishment if I don’t see her everyday?

Have you considered having your mom go to a Senior Center each day, or even a few days a week?

Is her depression being treated?

Tell her. Have a heart to heart conversation. Then help her find activities she can enjoy on her own or with a companion. She will only grow more dependent on you as time goes by. I can only imagine how hard it is to relocate at an advanced age and to be alone.
If she has the funds available try to find someone you can hire to run errands with her. Help her with food shopping, hairdresser etc. Perhaps a movie or dinner out. Or to watch a favorite tv program or help her with projects at home.
Establish boundaries. Choose a day you will visit and a couple of days for the companion. Is being lonely new for her in Ca? Was she lonely in Fl? What did she do in Fl that she enjoyed?
Does she drive? Is she able to go out on her own?
Give us more information and perhaps we will have better suggestions.

Sounds like my father. I took him out Sat. night. --- Later, Sunday night was upset about not going out. It's difficult to reason with him. I remember what i read about diverting attention, and we organized the dinning room table together. Sometimes, i find old songs he likes on youtube, to lift him spirits.
The thing is, we do what we can to help them, but we also need to take care of ourself.
Their depression doesn't allow them to be reasonable. But we all do what we can and thats more than good enough.

My husband and i go back to our place at night a few blocks away. My Dad  prefers we stay with him. But we need our own space. The advice on this site helps a lot to be strong.

How old is your mother?

What are her care needs? - you say you moved her from Florida to California so that you could look after her, but what were the concerns about how she was managing?

I feel so badly for you - my loved one was very much the same and made life as difficult as possible. No matter how frequently I'd visit, no matter how much I did, it never made any difference. The doctors and nurses were convinced that my loved one was suffering from depression, when in fact it was a response to having to go to a nursing home. My loved one just plain didn't like it. I've no doubt a part of it was depression, but most of it was being what my grandmother would have called "obtuse" and narcissism. There was no co-operation or effort to try. Medical staff thought pills were going to fix it (not). I realized after a lot of soul searching myself - me - and my loved one - that chronic unhappiness isn't depression.
I will say that if she still has her mind - if she's not suffering from dementia, she needs to take some responsibility for how she feels. I don't mean to sound too harsh...I can imagine what you're going through - honestly, it sounds like you're reading a page from my life story.

Has she always been unhappy and negative? If so, not sure what you can do other than what you are doing: being caring and also having boundaries.

Bamagirl, based on your added information, she has a more active social life than I do! You are to be commended for doing so much with her. It sounds as if she looks to you for any diversion. Was she always like this, I mean, did she always have to have others around or was she able to amuse herself? Is this new behavior? I would make an appointment with a geriatric doctor or psychiatrist because what she is taking is not working. My father has gone through periods of depression and was helped greatly by just low-dose medication.
I agree, if she is able to have such a conversation, tell her honestly how you feel. What you are doing already is wonderful. And I think it’s great that at 92 your mother is still able to live independently.

She lives in a Senior apt that has activities everyday. She chooses not to take part.
She is on medication for depression.
We moved her to Ca because she is 92 and could no longer drive. She is included in any family activity going on. We take her to lunch several times a week and she eats dinner several times a week with us. Take her shopping at least 2to 3x a week plus to get her hair done and nails.
She has all her faculties and very capable.
Just wish she would just try to be a little more pleasant.