my DP used to be like this, tbh I'm not sure if he changed or if I just stopped paying attention! For me I went downhill big time and one day woke up and said right, enough excuses, I'm going to make time to study no matter what is going on around me. It's amazing how that little thought was enough to make me focus on whet I needed to do and ignore DPs whinging/distractions/etc. It was as if I demanded the space and time and help to do what I needed to, and either he went along with it or I just didn't care anymore that he wasn't on board. Either way it's worked.
It's going to be hard but keep your eye on the prize and it will be worth it later. Good luck!