If you do nit complete your coursework, you'll get 0 for the component I should imagine.
I know how hard mental health is, I've struggled with it throughout my life and dropped out of secondary for a few years - so know what I'm going to say comes from a place that has been through it. You need to get a handle on this and try your best to finish - maybe try and break it down and tackle bits individually? It's not pleasant or fluffy advice, but it is honestly the best thing for your situation.
How long do you have to do it? Happy to try and help you find a manageable timetable - I know how hard this rut can be, but you'll be pleased to be done with it and the pressure of having it languishing incomplete will eat you. Don't save it until your resits next year - the pressure will return then. You can do this!