We are so sorry to hear of your and your friend’s loss.
It is permissible and even recommended to immerse despite the circumstances in order to allow physical contact between you and your husband, even if you are too sad to be intimate right now. A hug or other types of touch may give you comfort at this difficult time. You are permitted to engage in intimacy even if you are feeling sad or depressed, but be open with your husband about how you are feeling and whether you feel up for it.
May Hashem give you and your friend comfort.