Lack of empathy!!!

Lack of empathy seems to be the theme with my husband. I'm new to the forum but my husband was diagnosed nearly a year ago with rectal cancer (46).  For back ground when diagnosed they thought it was curable ..he went through surgery for a stoma then had intense chemotherapy followed by chemo radiotherapy. Then after all the treatment they said the cancer was resistant...it had spread to his liver and lung. Now stage 4. Incurable. 

1. He has suffered with mental illness for many years ...the year before diagnosed, he was going great. Swam 4 times a week, working and was on top of it. But it's been a total rollercoaster since the diagnosis and now since they've said it is incurable so much worse worse. I am trying to keep the house going, looking after the 2 children (10 and nearly 14) , continue to work and look after my husband but I am constantly told I have no empathy. I do not know how he feels. How can I? But I cannot fall to pieces for the sake of the children and for him. I need to stay strong and keep everything going but in his eyes I have no empathy!   I just would like to know if anyone else has felt this kind of backlash from their other halfs? It is emotionally draining... I am not a therapist and it is very hard when he talks so deep about how he feels. I try not to take it personally....but it comes up regularly how I am not dealing with it deeply enough.