Mona, I used the letter writing as a build up over time and only this past Friday actually said the words to my t verbally. You say your t does not like emailing between sessions. Would she read a letter in session that you gave her or with her tough love method, would she make you read it out loud or just summarize it?
Maybe the question to talk to her about is why do you let someone you care about treat you poorly?
I am new here so I don't know the whole story with your t, what I have seen leads me to feel like you deserve more. Have you ever felt like you were good enough in the relationships you discussed? Have you ever felt from someone else that you are enough just the way you are? I get the sense that you are not getting that from this t. It is some of what my t gives me and I think it was/is completely needed for me to get past the having to "be a good girl/kid" feeling. If you have not felt it at all, ever, then maybe finding a t that can give you that and work towards that so you can internalize it. <--- I'm not there yet, but there have been more moments of feeling that since working with my t.