Don't give up Brie ! I was 8 years from starting PPL to getting my first job.Been flying commercially for nearly 8 years now. Failed one sim assessment a couple of years ago.Why ? I think 'cos I fly glass cockpit and my 'conventional' scan is now non-existant !The check was on an older type,and it showed.I came out thinking I couldn't fly anymore.Of course I can,but I only fly 'well' on what I know and am familiar with.To fly anything different,and fly it 'well' I would need some practice.We are all human,and we are all different,but practice makes perfect.
Good luck,and don't give;you are not alone,even if it feels like it.
L8