Meds can help, but you have suffered a loss that can't be medicated away, and the only remedy for that is tincture of time. Eventually it will hurt a little less, and then a little less with the passage of each anniversary/birthday etc. You are already helping yourself by exercising---that's more than most depressed people can do! But I think you've still got some room to play with medications, even ECT if it comes to that.

Have you ever tried a four- or five-drug combination consisting of an antidepressant, mood stabilizer, antipsychotic, and benzodiazepine? It's what's helping me get through this business with my husband's cancer and poor prognosis.....I still get sad and upset, but it's a normal sad and upset and doesn't feel like my sanity is on the line every time I cry or have a down day.

Dunno if that's helpful in any way, but just know that I think of and pray for you.