I'm reminded of the old adage, "Fix the problem, not the blame".
Depression isn't really a "behavior" one can learn and I don't think he could learn being homebound for social anxiety from you if you are not homebound for social anxiety? It sounds like some of his problems are aggravating and maybe causing others; people who have heart operations often have to take anti-depressants afterwards because heart operations can cause depression! No, he probably doesn't have heart problems but the relationship of one body part to another and our subsequent physical/mental illnesses isn't very well understood yet.
http://www.washingtonpost.com/wp-dyn...062101934.html
No matter what, his illnesses and difficulties are his own; one person cannot know how another will react to any set of circumstances, that's partly why being a good parent can be so difficult; not only is there no training but there is no way to get any for any particular child as we are all unique in how we respond to things. Some anxious mothers have care-taking children, children who take charge too much because the mother doesn't; think of the "funny" reactions your children had when they were young and you wondered, "where did that come from?"
My granddaughter had a heart operation when she was 4 and woke up in the hospital with various tubes and monitors attached and her mother asked how she felt, did she want anything and she replied, "Yes, I want this, this, and this, gone! (all the tubes/connections, she pointed to each) This is the worst hotel I have ever stayed in; I'm never coming back!" (she had maybe stayed in a motel once in her life). Where did this 4 year old "learn" a response like that?
Your children are their own selves and are responding to their lives (and we can't really get into and understand those lives because of our age/generational differences, among other things) so our outlook and problems will always be different from our children's. Your son can't know/imagine what you have to face at work, much less "copy" your response to it. It doesn't fit him.