Mim, and all who have lost. Your boy sounds like such a treasure Mim x
Grief always get worse at first, its almost like at the very start you cant really believe it, it just doesnt seem real, and then the bitter reality of it sinks in and you just despair
. I don`t think the grief ever really goes away, but it consumes less of your daily thoughts as time goes on, and becomes more manageable.
Sometimes it is best to just do nothing, and not try to do anything. Not putting yourself under any pressure is important, I think. Obviously there are things you have to do, for your DD, work and so on, but the rest of the time, just let yourself be, and let yourself do nothing and grieve if you need to. You will be able to do things and focus again when you are ready, do not rush yourself beyond the essentials 
A while after PoleDogSr passed, when we were ready, the DC, DH and I all build a small memorial garden for him, and planted forget me nots. The physical effort of it, the talking about him and recounting memories of him really helped. It was a very sad thing to do, and I still feel sad when I sit on the bench there and think about him, but it helped to process the grief, particularly for my DC I think.
Thinking of you and everyone else x 