I think that bodybuilding, or any change (cosmetic or other) shouldn't be done in order to get someone specific, while it should be done if it helps you feel better about yourself and gain more self confidence. In your case I think that you should carry on with that, as it seems that helps you also to build up on the inside. But (and it's a big but), don't expect bodybuilding to do miracles. Being masculine doesn't necessarily mean that she will notice you all of a sudden. My approach in this cases, and this is based only on my personal experiences, is to come forward and introduce yourself, as simple as it sounds. You'll be amazed by the miracles that a simple friendly talk might do, especially if you are "chasing" her for a long period of time.