We all work diffrently

Yes, I'm depressed, And now I'm even on anti-depressants now. But that doesnt give people the right to just be mean to me, and personally attack me whenever they feel like it. Let me explain, I've had to resit an exam, and resubmit a piece of coursework in order to pass this year at uni (lack of motivation last time round I think), and so ive spent the bulk of my summer holidays so far, working on it. The big problem is, I find myself unable to concentrate on one thing for more than about 10-15 minutes without a 5 min brake, or a significant change to what I'm doing. Particularly since I started again with RSI in my wrist, because I have not been able to find an appropriate wrist rest. So, today while trying to work, my sister was shouting up the stairs to my mum, distracting me (I am easily distracted yes). I simply made a comment about trying to work and she verbally attacked me. She got got really aggressive saying that I was lying about working because she only ever sees me on skype and playing games. But she knows I cant concentrate for long. I'd really like to say I'm angry about this, but I'm really not, I'm just hurt and upset. I know when I'm like this, outwardly I appear very angry, but really, this has just made me want to curl up in the corner and cry. I am totally demotivated from working, and really, I just feel useless and like their is no point trying if that's all people see me as capable of doing.