It's all relative. You are living with your
situation; no one elses. To quote a line from my favorite piece of prose "If you compare yourself with others, you may become vain and bitter; for always there will be greater and lesser persons than yourself". You are in your own skin, so only you know how this is all affecting you emotionally. You already know the physical part
. I don't have any advice to try and impart to 'lessen the blow' of what's going on with you, but I will say this because I know you are a fighter: don't create a self fulfilling prophecy about losing everything. You may suprise yourself with how truly resilient you can be if you give yourself a chance. Don't give up dude, you haven't to this point and you're still going!
That sucks to have to deal with something else that affects balance when you already have MS. You must be like "c'mon already!". I hope you get to feeling stronger.