Boyfriend experiences anhedonia

My boyfriend said that he couldnt feel comfort or anything towards anyone whether it would be his family friends or me. Hes still receptive when I tell him to take his time and that Ill be here for him, he would thank me for that and all. Im wondering if you guys have any success stories, advice, treatment for anhedonia, or anything to keep me hopeful. Not only do I wish to see him get better for our relationship but it pains me so much that he cant enjoy his life and the flurry of emotions that come with it. I wish to see him flourish again.