Good luck, Sweetmissy. I hope everything works out for you. By the way, I can understand how the submissive role makes you more confident, but let me suggest that it is not so much the role as the relationship with your Amo. He obviously wants you and cares for you. He probably makes you feel like you are desirable whereas you current partner cheats on you, possibly making you feel like you aren't enough for him.
There is nothing like being wanted and loved by someone you love to make one feel on top of the world.