This is terrible advice.
OP needs to set boundaries in a paper traceable way after establishing then in person (an email of “dear boss lady, I want to eat lunch alone, kthxbye”), and track violations of those boundaries (dear boss lady, today you sat with me at lunch after I asked you not to, please explain why). (Obviously be more professional).
Then after a few violations, OP can go to HR because suddenly the boss lady is starting the fire; there is a clear history of personal boundaries not being maintained, leading to a hostile work environment.
This only doesn’t work when the company is like 5 people and HR is your boss’s cousin or whatever.
Can’t believe they showed one guy fucking another guys foreskin, that seemed really out of place