maybe believing that you have bad beliefs is another affirmation, maybe believing that the problem with girls is becasue your beliefs is an affirmation too, what if there is really nothing to fix?, it's just my opinion and my experience about affirmations, becasue i felt like adding more weight and running away of my own demons
well, as someone here once said (I don't remember who it was) we talk to ourselves all day long (usually negative shit) so why not 'change the record' to possitive.
I guess gratitude is also good to remind yourself what you do have.
And regarding the negative self talk- it's based on our past experiences (and we all have those....). So unless you can be in the now moment and control your thoughts it's kind of hard you know....
even monks have to train for years before they can silence their thoughts and be in the now most of the time.
edit: I did mention that I use the Sedona to release past baggage and not use affirmations as a band-aid