Ankle Sprain not healing

I was in a car crash in Nov 2015 where someone hit me head on at 60mph. I sprained my right ankle on impact as it turned inwards and upwards I think so mainly affected the ligaments on the outside. Not sure if it was a Grade 1 or 2 but I was on crutches for 4-5 weeks. I initially had physio which helped to a point but I still get an acute pinching type pain if I put weight on it in the wrong place - for instance just walking or reaching for something. I recently had an MRI and the surgeon said he could see the evidence of the sprain and there was some bruising to the bone but that there was nothing he could do other than refer for more physio, which may or may not help.

I am confused what I should / shouldn't be doing so my question is:
Should I be trying to do strengthening exercises regardless that it is painful or should I be resting it and avoiding the activities which cause pain (i.e. Not walking as much)?
And could I potentially be left with unresolved pain from this accident? When I saw the consultant via the insurance he said he didn't think there was permanent damage but it was over a year ago so realistically is it going to heal now?

I would be grateful for any advice on this. Thanks