It is tricky but the only way to do it is to do it.
You say that you areready to make the changes in yourself. Does this mean that yyou have not actually started to make those changes and if not, why not?
There come a point where you just realize that you have to move forward. Moving forward does not necessarily mean walking away. You decide how you will move forward.
Time is your friend. Some things take time - healing, forward movement, change, reconsidering a stance, reopening of doors which were shut. Walking away may be the only option your H sees NOW. In time, he may or may not change his mind. Time is the key.