I am so sorry for your loss. I think each of us grieves differently and I do think therapy is helpful.
For me changing my perspective helped some. What would my deceased loved one want for me? He would have wanted me to live my life, he would not have wanted me to be unbearably sad. I also found ways to honor him, and sometimes when having a particularly good time I still say "xxxx would have loved this."
Mostly just be kind to yourself, this is never easy. Hugs ❤️