Not trying to invalidate you, saluki, just picking up on something you said: "mechanism for avoiding..."

I used to worry constantly about what might be "really" going on for me that I was perhaps "repressing" or using "defense mechanisms" to avoid -- only there seemed to be no end to it. I'd figure out one thing (which always felt like it had to be an insignificant part of the whole, not even the tip of the iceberg)... and whatever I figured out would raise way more questions than it answered. "I must be doing A to avoid B and C, but then what are B and C about?"

Nowadays I prefer to look for alternative stories that could fit the same set of facts. This might be one such; I'd be curious how it fits you, or doesn't:

Imaginary quote
----------------------------------------------------
Not actually posted by salukigirl

When I have a choice of talking about my
depression or coming up with something
funny, I often choose humor.
----------------------------------------------------

You're still free to make up a story (or several) about why you choose humor, what it says about you that you do, what might be behind it all, or what Freud would think if he knew; but now that's a separate story and no longer a necessary accompaniment to your observation that you sometimes choose humor. I'll even say: you're free to choose or unchoose either story, just as you're free to choose or unchoose humor.
I don't see why you couldn't be hilarious even while you were noticing your true emotions (and choosing when/how/where to express them). For me, drinking coffee isn't a cover up for replying to your post -- I can type with one hand and hold the cup with the other. I don't happen to feel depressed at the moment but I'm pretty sure that if I did, I'd much rather be hilarious than, say, miserable about it. I've always found being miserable about depression awfully, well... depressing.