4. Bg5 has no threat or purpose. You were better off with Bg2 and 0-0. And preparing for counter-play with c4, etc.
6. Bf4 costs you time. Losing time is a subtle positional factor, but you must be aware of it during your game. By attacking your bishop a second time (g5), black gains more space and, if black were to castle 0-0-0, his attack on your kingside has already started.
9. a3 is a failure to see a tactic. Clearly the knight is not intending to stay on b4 for long, so a3 is another wasted move. Better was Rac1.
Please help, Im still lost as to where I went wrong. I played the ending bad, but I went wrong somewhere in the middle game. Thanks guys.... Jay