Hey Mr.Blank,
It's a tough situation to be sure.
I, for one, think the best action would have been to continue your N/C like everyone advised. I say that because it seems like you are telling her what displeases you and your not excited about what direction she is heading towards. Also, if your not readyto get back together what's the point in all this? You seem to be opening wounds that you began healing.
I do understand why you did it, I did the same thing. I called after the relationship to clear the air and said some things I wanted to say, she did too and we got nowhere. What I'm saying is thatyou must look at the bigger picture. Do you want her back, HONESTLY want her back, not just cause your lonely. If that be the case than this could be your opportunity for that. If you plan on not taking her back (although this still is not your choice at this point) than you need not say it is too difficult but rather begin a new N/C and let this go.
5 months is along time for N/C and bringing herback will delay getting over her should things not result in getting back with her. Find out what you want and simplify, if you want her go! If not than enough talk, never mind whether it is childish or not to not pick up. I'll bet in 5 years you really won't be concerned with whether not picking up was childish.
Sometimes we put too much faith in what we want to get and ignore the benefits of what we don't get. There are benefits in not getting something my friend.