I am so very sorry you are feeling so down. Holidays can be hard without a loss of a loved one, so having to deal with a loss can be more debilitating. Take your time in your healing, there is no set rule about the amount of time you need to grieve.
Can you take a little time each day and only "spend it with Andy" and then tend to what the days brings? This can be your special time.
Sending you a