I can sympathize, I've just been writing songs in the last few months as a brain exercise -- doing something I've never done before because I don't want to get stuck in a thinking rut, but also because I enjoy singing to myself and want to try new/old ways to express ideas that don't seem to fit any other form.
Still, even though I'm a true "dabbler", I want the songs that I do write to be good ones. I've tried sending the lyrics and midis (created using Noteworthy Composer) to my father, and he has one criticism of everything I've written so far: that the rhythm of the melody doesn't match the words -- that I have too many notes, or too few -- that the whole thing just sounds wrong. Meanwhile, because I've written it using NWC, I know that the notes and syllables match up -- though I concede that maybe I've used notes of the wrong duration for specific syllables, even though it sounds right to me.
I just don't hear what my father hears, and he doesn't have the language to explain it to me... he has tried to play the melody of some of my songs for me on a small midi keyboard, to show me what he hears.... But he doesn't play the piano, and he can't play the rhythm as it should be, because he's henpecking the keyboard looking for the right notes.
I trust my father to be honest with me, and I value his opinion, but the frustrating thing is that the experience of music is so subjective. And even a specific, constructive criticism beyond "nice" or "it sucks" doesn't do much good if the critiquer can't give an alternative ("Maybe if you tried ____ instead"). I've found this to be true in other creative fields as well, particularly in non-musical writing, but also the visual arts.
Maybe that's why your friends don't give you more constructive criticism, Jeri -- they don't know how.
We have HMTL Practice threads on Mudcat... I don't see why we couldn't also have songwriting practice threads, especially with the midi-to-texts and text-to-midis programs that Alan Foster created. If the Mudcat community has one thing, it's musicians who know how to communicate!