The BMA is the professional association/trade union for doctors in the UK, and looks after the professional and personal needs of its members. It can help you with any difficulties or disputes with your employer, and there are local representatives who can meet with you and support you through difficult times. It can provide advice on a wide range of issues, and is a really good first port of call.
The website provides a wealth of information on a range of issues affecting doctors, including health and legal matters. They list the contact details for a wide range of resources for doctors in difficulty. You can even talk to an advisor online if you don’t want to ring or email!