I think you are fantastically well, look at how consistent you are at losing weight.
As for the groups, I was under the impression they should mix new with existing members as it defeats the object and only means you have to continuously go over what you have already. That said, my LLC always mentions you shouldnt join to new members but continues to allow them to join the group. I started with a group of about 8 ladies, there has been a consistent 5 along the way as some have stopped the group or there are new members. Luckily the LLC doesnt go back over the previous modules so it isnt impacting too much. However I agree it is difficult to bare your soul in front of people you havent jelled with yet.
Hope you have a good day xx