Question?

oh yeah, at the beginning, everyone tries to put you off, it's only because you are doing something about it and they aren't quite there yet and are a little envious.
You gotta ask yourself, do you want to live and be healthy and is that more important than a few jibes about what you eat, cos mark my words, as the pounds fall off they'll soon shush!
Good luck to your boyfriend, he can do this!

Only women. But it's in their nature to attack others instead of doing for themselves

They are just jealous. From my experience they are only acting that way for 2 reasons: 1) they want to do it, but don't have the willpower or knowledge 2) they don't want to be alone in their unhealthy habits (misery lives company), and they naturally resort to mocking and ridicule to bring you back to the dark side with them. The interesting part is that you will probably find the people who are mocking you the most will likely end up asking you a lot of questions and becoming interested once they start seeing the results and benefits of your new healthy choices and may even jump on board. People are weird, just ignore them and wait it out and remember you are making healthy changes for yourself, not other people, and your real friends will support that.