I have over 20 years of experience in this industry and have helped navigate tricky issues for friends and others. Whenever, I see these questions, it breaks my heart, so let me add my advice.
ALWAYS BE DOCUMENTING
As others have said that you should document your managers' behavior, but I recommend start documenting it on day 1. You can call it journaling, if you prefer. You should record, who did or said what and who was present. Try to be objective.
The easiest way to document is email, email to your personal email. Make sure to not include any secrets. Another option is CRM like Monica, this may make things more organized but is harder to use.
NEVER EVER BE PUSHOVER
Never give up your personal time for work. If you are asked to work late or over weekend, just say you have plans. Sometimes that is all you need, sometimes they will ask for more details, just say it is private. Unfortunately, some managers will still try to get more info. A little bit of cultural training will help (this is sensitive topic and may not apply to everyone but it is good to know background of your managers, so you can deal with them in respectful ways of their culture, see below).
CULTURAL SENSITIVITY
In strict hierarchical cultures, saying no to manager is unthinkable. I have seen it first-hand where if manager's wishes are not met, they will throw a tantrum, yell, curse, get HR and their managers involved. It can get real ugly very soon. When dealing with managers from such cultures, I would be very apologetic and show a little too much respect. Sometimes, it is even better to agree and then just not do whatever it is. It is all about appearances.
Another interesting cultural difference is amount of privacy that some cultures have or lack. In India, people are very open, so if you say it is private, they will still keep asking you what it is and they may even help you change your plans. My friend's manager helped him sell his tickets on eBay so that he can work. Never reveal your plans or lack of plans to these kind of managers.
On other hand, American and Western managers are a lot more politically and socially savy. They don't really try to use hierarchy to boss people around as much. They are the most dangerous of them all. They develop what seems like real friendship with their subordinates, they have lunches with them, host happy hours, invite them to their parties etc. But then they ask favors to be returned in the form of long hours at the work. I would consider every moment spent with them as work and reject at least 50% of their social invitations.
Of course, every individual is different and you should try to understand them at individual level.
ALWAYS BE INTERVIEWING
Interview once every year. This will keep you sharp and aware of market situations.
ALWAYS BE SAVING
A lot of people stop becoming pushover as their savings grow. Save enough money to last you, at least, 6 months.
LEARN LEGAL AND HR TERMS
Telling HR that you are feeling tense or about lack of work-life-balance is meaningless. But if work is affecting your Mental Health, causing you stress or anxiety, this will get their attention. I had a colleague whose manager was being abusive, took a several weeks of paid disability leave because his mental health was deteriorating, or he used right terms. Not only that but his manager got in trouble for causing it.
READ BOOKS ON MANAGEMENT & POWER
Never Split the Difference, 48 Laws of Power, etc
EDIT:
In your specific case, my recommendation, is document as much as possible. Who did what and who was present as witness.
Next look up your company's insurance/policies and see if you can get on disability leave due to mental health. Even if you cannot, file some paperwork.
Reject 7PM calls, say you have a family situation.
Of course, consult a lawyer.