I think it's right that habit is a big part. Look at food. We tend to like what we were used to eating as children.

And some things clearly affect us.

But sometimes therapists' explanations are so far fetched, like this and that behavior from a parent will lead to this or that problem. Sometimes it is kind of clear, if your parents have been unstable and sometimes there sometimes not, you might grow up to be scared of being abandoned. Not exactly rocket science. But it really ticks me off when they start analyze things like Oh you're depressed because this and that happened and you yourself think it was nothing big but they are "sure" they found the key. Or that you are scared of spiders because they are a symbol of your mom.

I can still tell my parents were not to blame for the issues I encountered in life. In many ways, they might actually helped me with my strengths, but no one ever sees it that way, do they?