Wife have moved out with my son..........now what

[nw626]

I spent another good weekend with my son, but that 6 HRs drive is getting old.
It was also my W's mom birthday. We had a small celebration without my W. It was really strange.
MIL and I are pretty sure the A is done and over. I haven't seen her close to 2 months now. I miss her a lot. She and I are now more like casual friends. We only talked about our son when we communicated. She actually email me and thank me for her mom birthday stuff. She sent me several new pictures of our son.

At the last part, this is what she wrote...
I am not sure what the next step in this process is, but I guess one of us needs to file for a legal separation. I don't think I can do it here since I haven't qualified for 'residency'. But, the laws are same here as they are in GA. I will find out what needs to be done and let you know. Thanks again for everything and call Boo Boo anytime here, at my Sis's or Momma's or my cell phone. You can always reach us at someone's house. Take care.

It seems like she is not turning around. I feel pretty down after reading this.

Should I even bother to reply? She knows how I feel. She knows I want to work on our M.
Or should I just do a 180...saying. "I understand and respect your decision, but I don't agree with it. Please let me know how I can help."