There are a few approaches I think you could try
First approach: look through your rants and find one or two lines that you really like - this will be your hook. This line is normally best placed at the end of the chorus, so start thinking about some more lines that could build up to it - once you've done this, you've written your chorus. Now build your verses, which can be either the hardest or easiest part depending on the song.
Second approach: Make the music first, if you play guitar just start jamming out a riff or chord progression. Play it over and over until it's automatic, and then just start humming melodies over the top. After a while start singing the odd word of isolated line - don't worry too much about meaning at this stage, you're just jamming. You can always fine tune the lyrics later.
Third approach: Write the lyrics first, figure out the meaning later. By this I mean just try playing with words to find a clever or powerful line that can become a hook.
I would also recommend closely listening to lots of music, especially artists known for their lyrics. I don't know what your tastes are but Simon and Garfunkel, Ed Sheeran, Pink Floyd, Leonard Cohen, Jeff Buckley, Bob Dylan and John Lennon are all excellent lyricists. Really think about how the lines are arranged, the rhyming pattern and on which words the emphasis lies.
As a final piece of advice, try writing first about topics that aren't as personal - a slight detachment from the song you're writing can help hone your songwriting skills. I know when I was starting out, any song I wrote that I had any emotional connection too was basically a mindless scribble on the page. Write some generic love song or something.
Hope this helped