Abel is going to kill Jax, not Gemma. Gemma will then be forced to live by herself as Jimmy Smits leaves herJust came to say this.
It's obvious that Abel is going to shoot/stab Gemma at some point. Jax is going to realize all of the current wrongs and he will either take his kids and go away or die and they go with what's-her-name.
Post-scene will show An 18 year old Abel joining the chapter in some other town and the cycle begins anew.