I got suspended from work. Advice?

I made a simple mistake (sent correspondence via email rather than post) and have been suspended whilst they investigate.

This seems harsh. My company has beeen giving me shit for a year now.

I was hit by a stolen car and left with brain injuries about a year ago. My manager said I was lying amd I'm too scared to work then put me on a disiplinary for handing in a sick note.

I obviously argued back and ever since then it has been a shower of shite. I feel like I cant fart without them critiquing the way I do it. Other colleague have noted that they treat me harshly too.

I'm not even sure what I am asking here but what would you guys do in this situation?