I used to have the same problem...sort of! From the time I started lessons until the time I bought my first horse, I rode with my toes out. Not a lot, but I did a lot of jumping in my lessons, and they kind of just stuck that way. Then I started taking dressage lessons and my instructor was always on my case about how my toes needed to point straight forward. It hurt like crazy for awhile but eventually I got used to it. Now it hurts like crazy to ride with my toes out even slightly.
I just had to make a conscious effort to change my position and it got easier and easier until it was unconscious. Not a quick fix, but just know that it will get easier!