It’s possible that you are suffering from incomplete grieving. You were already depressed when your mother died. It’s possible that you couldn’t bear to feel the feelings of loss on top of the depression. You therefore coped by shutting off all of your feelings. That may have been a useful strategy for a short time but now you can’t seem to pull yourself out of it.
A therapist can provide you with the emotional safety net you need to pull out your feelings. It will be difficult to feel them. But you’ve already come to terms with the fact that the way you are living now isn’t a solution. With the support and guidance of a therapist, you can gradually let yourself feel what you need to feel and not be overwhelmed by it.
Please take care of yourself and get the help you need. You deserve it.
I wish you well.