Welcome to the forums and congratulations on your successes so far.
I think being obsessed to a small degree is a good thing, as not paying attention to what we ate is what got us into trouble in the first place. However I would be concerned if your obsession is causing you to not eat enough.
Some of the things that you may want to look at are ..
How much weight are you loosing? Are you dropping more than the recommended amount?
Are you getting 100% of the recommended daily amounts of your nutrients?
How do you feel? Do you have enough energy? Are you getting headaches, etc?
If you aren't having any problems I wouldn't worry about being obsessed but if you start having issues it's time to see a professional.
Starting Weight - 295 - 09-Feb-11
April Fool's Goal - 180
Current Weight - 201