Found out about my girlfriend's past (25M and 23F)

I need some honest advice about my relationship because I’ve just learned some things I can’t ignore.

A bit of context: I (25M) dated my current girlfriend(23F) briefly back in 2021 (about two months). We broke up after she went on a date with another guy I was uncomfortable with. I got upset, she said I was overreacting, and ended things the next day. She ended up getting with that same guy immediately after.

Fast forward to recently, she reached out to me out of nowhere, asking about work at the office, it escalated and we started talking again, and now we’re back in a relationship.

Here’s where things get complicated. A coworker of mine, who used to be her classmate at the University, found out I knew her and she shared some things about her past behavior.

According to her:

My girlfriend was in a relationship with a guy from her class but cheated on him and left him for someone “doing better.”

She reportedly has a pattern of moving on to guys who are better off financially, then losing interest and acting hot-and-cold.

When that same ex started dating my coworker, she would interfere, even physically inserting herself between them, grabbing him, and generally overstepping boundaries despite knowing they were together.

She was also described as overly familiar with lecturers and very attention-seeking in ways that made others uncomfortable.

She had multiple relationships and seemed to enjoy showing off a “high lifestyle.”

The most shocking claim was that during one relationship, her boyfriend at the time found out she had been had sex with half the class.

On top of that, she still occasionally contacts my coworker’s ex (the same guy involved in that situation).

Now I’m stuck. On one hand, this is all second-hand information, but it’s coming from someone I trust and who doesn’t seem to have a reason to lie. On the other hand, some of it lines up with what I’ve personally seen in the past.

How would you handle this? Would you confront her directly? Take a step back? Or walk away entirely?

I’d appreciate honest opinions.