Student Finance: Not including Partners income?

Long story short. Parents split last year. Mum has now moved in with her BF. Using their sum household income means I won't receive enough from Student Finance to be able to fund my studies (I'm going abroad next year as well).

I want to complete my degree, but even with the max loan and me working 20-30hrs weeks right now living is hard. I won't have the finances to live if I include my Mum's bf as part of my household composition as he won't offer a penny (why should he?) and my Mum doesn't earn a lot. Meaning liklihood is I would have to withdraw.

Unless there's anything I can do, I'm feel faced with no other option but to just list my Mum. I want to know that if I were to do this, what evidence might they ask for to show she's single?

Also is there absolutely no way Student Finance have some exceptional circumstances for people in my situation. I'm ****ed if I don't get this loan and will likely have to up my hours to 40-50hr weeks (if my employer lets me) if all goes bad. That means missing all my lectures - I will do anything to get my degree.