To echo some of the above comments, it sounds like you are over-analysing when it comes to songwriting. To get back on track you need to engage your Feeling functions. I suggest you first do something really enjoyable to get yourself into the right frame of mind, then just write down what comes naturally in a free-form, flowing stream of lyrics. Complete the song first, then go back and make any desired edits, or better yet, get someone whose opinion you value to look at it for you. This will allow your Fe function to contribute to the process. Not much will happen until you give yourself the freedom to work in this way, I suspect.