[informatimago]

Clearly, your exgf was a gold digger and she assessed (probably correctly) that you bank account was now worthless, and that your startup employer won't be the next unicorn.

The anxiety you got from your job is probably also a sign of the same thing, unconscious in your case.

Probably not entirely your fault, I guess there are more people involved in your startup employer.

I would say, share the pain: resign from your job, and find a better one.