I think in your situation, I would tell him, but for his sake not until he is back and you can do it in person. I think I would really have a tough time knowing my wife was going through this and not being able to do anything in person to help.
I am glad you are getting help and wish you the best. Be tough and know the next few weeks will suck, but will eventually end.
PF
Me; 42, W; 43 M; 16 yrs S12, D9
3/13 - "I want to move to XYZ City (four hours away) and it might be without you, not sure" 5/13 - "Not sure I meant that"