PIP reassessment fears

I am 32 years old and was only diagnosed at 27.  I briefly had a job which didn't work out due to not being able to cope with dealing with customers and applied for Universal Credit and PIP 3 years ago.  I was initially turned down for PIP, did the Mandatory Reconsideration, then pursued it all the way to court where, with the support of my mother, I was awarded PIP and given a high rating because of my poor social skills and inability to plan and follow a journey.  I have just had the letter and phone call about the three-yearly reassessment, and I am really worried that I'm not strong enough mentally to go through this process again.  Does anyone know about it?  Will I have to go back to court again?  Is there any advice you can give me?  Thank you