I don't think it's inappropriate unless it becomes the main focus of therapy. I kind of wish my therapist talked about himself more because I like hearing his stories and getting to know him. Sometimes I have been jealous, but I've never been mad that he had great experiences so much as I've mourned my own lack of experiences. For example, my therapist seems to have many friends and acquaintances, he is much more extraverted and outgoing than me... I've always been jealous of this but at the same time I love that he is not isolated as I have been, I just hate how it reminds me that I'm weird. It makes me feel like more of a normal person when he shares things about himself. It makes therapy seem less clinical. It helps me form a picture of who he is, I think it would be hard for me to self disclose anything to a blank slate.