I think the ability to overcome the phobia depends upon the level of desire you have to do so. I used to be so phobic of spiders and cockroaches that it really was impacting my daily life. eg: Couldn't hang clothes on the line because there were often spiders there, had to leave the house if I saw a roach until my husband could find it and kill it.
I once spent a whole night locked in the third bedroom in our house (which was the craft room) with a towel shoved under the door and I sat and watched the door until my husband came home and disposed of the roach that had been running around the house.
This level of disfunction eventually got to me, so I decided I was going to take control. It start with launching large heavy projectiles from across the room in the beginning, to now I can actually get close enough to whack one with a shoe. (For info, thongs are the best, because they are easy to hold, flat on the sole and the flex gives a nice whack.) I can now kill relatively large spiders with fly spray, however I haven't been confronted with a large fast moving spider like a huntsman, that one is still causing me a large amount of anxiety.
But I am also claustrophobic, cannot go into caves, have difficulty in elevators (panic attacks are now rare, but do still occasionally happen). Basically I have learned to control the fear, but it's still there. But I have no desire whatsoever to fix it completely, because I would need to go into caves or other tight spaces and I don't want to, it's not affecting my daily life too much, so I don't feel I need to address it.
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swingingstories