Hi,
I am bullied too, I am desperate to quit, but I can't afford to, and finding another job is taking ages. Last year, I took a credit card, my first one ever: I had been considering resigning and leaving on the credit for a while, but it would only cover my expenses for about 2 months and a half, maximum 3 months.
Like you, I am overloaded with work, and do a lot of overtime (up to 3 hours a day). My colleagues on the other hand... Booking time off for interviews is a nightmare!
Unlike you, I am not supported at all by my managers (direct + senior). They support my bully, who they hired 6 months before me and who they are grooming for a manager role. In fact, I think they hired me specifically so that she could bully me, to increase her self-confidence! I can't go to HR because one reason for the bullying is that I am not British, and the company (Australian but British staff) is extremely racist. For example, we foreigners are not allowed to have lunch with our colleagues, we are not invited to the Xmas party (or to evenings out), we are paid far less for the same jobs, and inside a department, we mostly do the drudge work, except when our colleagues go on holiday.
You are very lucky that your senior manager and HR seem to be supportive. However, possible reasons why they talked you out of resigning is that they didn't want to look bad, your department is very busy and they wanted to have the time to train your successor, they knew you were going to leave anyway (on maternity leave if you get pregnant) and were half-expecting that you would not come back after the leave. Last year, I asked to go part-time, after several 'success factors' interviews where my managers told me that they did not expect me 'to remain in the UK another 12 to 24 months'. My managers refused and tried instead to get me to write a resignation letter. They wanted a date for my departure from the company. I had numerous interviews with them, and 2 months after I sub