I was GNM, I've played about 15 matches since returning. Won one. Silver II now.
Can't see how I can even enjoy playing at this level tbh. Think I'm done.
Just play with people off the forums and you will be back to your old rank in no time.
If its really been six months, then you won't have played since the big rank reshuffle, so you are probably around GN2 anyway, so its not that big a task to get back up.