Surgery for insfraspinatus repair?

I've have shoulder pain for about nine months. Rehab nor rest worked. Limited power, cannot do front rowing on reformer, for example. But functionally it's okay, apart from pain (worse at night). My suspicion of damage to infraspinatus confirmed by MRI. Complete tear, about 3cm. Surgeon says it can be reattached to bone, but I'd be in sling for 6 weeks and need further 6 weeks to rebuild muscles. Can't decide. Has anyone here had shoulder repair surgery or should I keep working to build strength around area? Thanks! Eimear