I've written a few - but mostly they are not personal to me, more like stories. I've performed my own songs at an open-mic thing & they went across OK - but I wouldn't want to do exclusively my own stuff as its asking a lot of an audience to pay attention to something they've not heard before & which has no familiar bits to latch onto. I've only written two that were about how I feel. One was for Hammerite when she was about 3 years old, and its very gentle & sweet.
The other is very recent & was written as therapy to stop me getting really wound up about someone. There's a woman I know that really can't stand me and I've no idea why - I don't think I've ever done anything to upset her. Anyway, its got to the stage where she explicitly goes out of her way to ignore me, and I started not to find it so funny anymore. My dad told me to 'let it go' & so I wrote a song along those lines, and now I am totally cured!! She probably still hates me, but now I really don't mind.
I am totally amazed at the power of a song to support & reinforce a particular state of mind & I begin to see how songs can be such effective propaganda...
I probably shall sing it at a pub session soon (and most likely with her in the room - but not in a vindictive spirit - she won't know its about her).
Not sure what markets are where for what - but that's OK because I'm not selling anything.

Kris