You mentioned that when you came in for your interview you were attracted to your soon-to-be boss. That is a red flag right there and in my opinion you shouldn't have taken the job. However, what's done is done, and now you have to work for this man, so my advice is to keep it professional. He is your boss, not your friend, so don't get friendly with him and do not add him to Facebook. The only reply to the text should be a simple "thank you".
I would only interact with him at work when you have to and not find every reason under the son to talk to him. If you feel that the attraction is too strong, then the responsible thing to do is find another job. Good luck to you!