Perhaps if you just tell him that this is hard, you are hurting, you didn't realize that his lack of attention for you right now would wound you this much BUT make it clear you do not expect him to fix it. The situation is what is and he can't do anything about it. He can't make it better right now.
I find when I am in situations similar to yours - I hurt but it's no one's fault and can't be fixed or resolved right now (or maybe ever) - it helps to have that hurt acknowledged by the other person involved. Also don't dwell on the hurt with him - since he can't do anything about it except acknowledge it - that would be cruel for both of you.
Hold on. It won't be forever.