英语翻译我给你写这封信是因为我有一些难以启齿的事想要和你坦白.（求翻译得真诚一点,一定要突出难以启齿的这个意思来!然后不

其实hart to tell和unspeakable都有难以启齿,羞于启齿的意思.
I write this to you because I have something unspeakable to let you know/tell you.
I write this to you because I indeed have something hard to tell.
如果你不想表达正在写信的直接感官就不必要用I am writing this to you了,另外其实tell you也蛮好用的,过度的修饰反而没有直白的效果好.

I am writing to you to confess. I am afraid I am not good at expressing myself face to face. That's why I have to pick up my pen and confess.

I am writing to you because I have something that is so hard to say to confess to you.