HI Wahine
Has been a while since I checked the boards and this is a great thread to welcome me back.
I think you should be able to smash your preconceived ideas of your "self" and come out ever stronger on the other end of your journey- It is great to see you - and others on the board- strive to crumble those barriers! Seems the self made barriers are the toughest to push over!

As an aside/ observation- while I was learning to lactate balance point testing the fellow running the course was retelling a story of "Juerg". He is an olympic level coach and he wanted to know how many hours his athletes could train at -20LBP and still show improvement. So he had them rotate between rowing, cycling, running 2 hrs each- For a week they just rotated among those three ( all this was closely monitored with blood work etc- and he found his athletes could train at -20LBP- for 8, that is eight hours per day and still show the benefits ie improved aerobic capacity with out the injuries/breakdown.
So keep your heartrate 20 beats below your lactate balance point and you can train away ...watching the bricks of the self imposed barrier tumble one by one