Going dark and everything really is about you. You can't think of it as a way to change H or a way to get back at him. It is just you taking time for you so if you don't respond to him that is ok because he will get over it with time. My H for a while would text and I would always text him back because I feel it is rude to not answer someone (I hate when he does it to me), but then I decided to only answer if he asked a question. He soon learned if he wanted a reply to ask a question.
About his normal text, "I don't know what to do". Think of some ways to respond that would be different and use them every time. Things that don't put everything back on you. Say something like "I am sorry, but I have complete confidence you will figure it out". This puts everything back on H. He is the one who left and he has to be the one to choose to come home. Also this also shows him that you want to be his partner and not his mom. He is a big boy and can handle his own decisions. You have to have something ready so that you can not fall for the bait.
Have a good weekend!
Me29 S3 H left 4/1/09 I file 8/2/10 Divorce final 5/17/11 1st http://www.tinyurl.com/25lhu52 2nd http://www.tinyurl.com/2c35ueg 3rd http://www.tinyurl.com/322yk89