Feeling sad while undergoing fertility treatment

I’ve had a lot of ups and downs with fertility treatment. Mostly downs. Because it hasn’t been successful, I’ve been feeling very discouraged and down a lot of the time. While I allow myself to feel the depression, sadness and discouragement, I’m finding the negative emotions so overwhelming and consistent that I’m having trouble finding any good thoughts to keep me going on this journey. I don’t really know what else to do. I feel so negatively all the time and hopeless. Intentional models haven’t been very effective so far.