My manager has been trying to push me out for over a year, and my boss keeps apologizing instead of stopping it. Am I overreacting?

I’ve worked at my company for over 4½ years, which is much longer than my current manager. I was trained directly by the owner from day one and learned almost every part of the business over the years. Because of that, the owner often asked for my opinion on things and trusted me with training new employees.
As the company grew, we moved into a much larger office. The owner let everyone set up their workspace however they wanted, and I decorated my office and made it my own.
Eventually, the owner decided he needed an office manager because he traveled frequently. He even asked me if I wanted the position, but I turned it down because I knew I wasn’t the right fit. I wasn’t interested in being responsible for opening the office every morning or managing everyone.
He eventually hired someone else.
From the day I met her, something felt off.
When the owner introduced us, he mentioned that I had been with the company for years and knew the business well. Instead of taking it as a normal introduction, she seemed to become irritated almost immediately.
A small example: after I came back from vacation, I jokingly wrote “Y’all’s favorite gal is back” on my whiteboard. It was an inside joke with my coworkers. She immediately corrected me and said, “No, everyone is the favorite.” It was such a small thing, but it felt like she took it personally.
Not long after that, she became very focused on getting me out of my office.
At the time, she had become close with our front desk employee. Unknown to me, they apparently came up with a plan to move me to the front desk so someone else could use my office.
One day, my boss asked if I could temporarily help cover the front desk because they were behind on work. I agreed.
Then one of my coworkers quietly pulled me aside and told me this wasn’t temporary—they were actually trying to move me out of my office permanently.
I immediately told my boss I wasn’t comfortable with that.
The new hire (who wasn’t even officially the manager yet) then tried to lecture me about respecting my elders and claimed the owner wanted me to close my office permanently.
The problem?
He never said that.
Later, before leaving on another business trip, my boss held a staff meeting.
During that meeting, she actually asked him, “Should we close her office?”
He looked confused and responded, “What? That’s her office. Why would we close it?”
That should have ended the issue.
It didn’t.
After she officially became manager, things got worse.
She constantly complained about me to the owner, saying I didn’t work hard, didn’t listen to her, and even brought up that I was sometimes late.
To be fair, I have struggled with being late at times. I’m not going to pretend I’m perfect. But despite that, I always completed my work, and the owner knew the quality of my work because he had trained me himself.
Every time she complained about me, the owner would later tell me, “I know your work. Just keep doing your job.”
She also started making changes around the office that hurt morale. She discouraged coworkers from talking to each other, told people not to eat at their desks, and wanted clients coming into the office as little as possible. The office went from feeling relaxed and friendly to feeling tense.
Then came the scheduling issue.
The owner personally asked me to work weekends because he noticed my hours had become shorter.
While he was away, the manager told me the owner no longer wanted me working weekends.
I believed her.
That same weekend, the owner came into the office asking where I was.
One of my coworkers explained that the manager had removed me from the schedule.
The owner apologized to me personally and put me back on weekends.
She took me off again.
He put me back.
She took me off again.
This happened more than once.
Then came what really crossed the line.
One Friday I called in sick.
While I was home, she instructed another employee to go into my office and pack up all of my belongings so they could move me.
Thankfully, another coworker stopped them and immediately called me.
The employee she ordered to move my things even texted me apologizing because he was uncomfortable and was only following instructions.
When I confronted her, she claimed the owner had approved moving my office.
I already knew that wasn’t true because I had spoken to him the day before.
I told her very clearly:
“Do not touch my belongings unless the owner tells me himself. If you move my things without my permission, we’re going to have a serious problem.”
She threatened to call the owner to prove herself.
She never did.
Since then, I’ve stopped engaging with her unless it’s absolutely necessary for work. I don’t argue with her, I don’t gossip about her, and I don’t try to get her fired.
Ironically, another employee actually asked me to help get her fired. I refused because I didn’t think that was the right thing to do. I figured the owner should make his own decisions.
Here’s what confuses me…
The owner has apologized to me multiple times.
He has corrected her after she falsely claimed to be following his instructions.
He knows she changed my schedule without his approval.
He knows she tried to move my office without telling me.
Yet she’s still the manager.
So now I simply keep my distance and only communicate with her when absolutely necessary.
Am I overreacting for no longer trusting my manager after everything that’s happened?