I didn't understand a lot of your post, I'm sorry to say.
What I get out of it is that you thought you had something romantic with this guy, but you found out that he is in a relationship and has been for a year. You are upset that he didn't tell you, however, nothing physical has happened between you (at least not in the past two years). Am I correct?
If that is the case then yeah I do think you are a little slow. No offense. I just think you assumed a lot and expected a lot. Should he have told you that he was with someone and had a baby? I don't know. I find it odd that he wouldn't tell you this if you were friends, but at the same time, if he didn't think anything romantic was going on between you, then it's not really information that you need to know.
"i just feel this is another repeat where i let my feelings for someone blind me to everything else"
This could be true. When you want something, you should go and get it. You can't spend 10 months flirting with someone and assuming you have some kind of relationship - At some point you have to be straightforward.
How are things coming along?