Unfortunately, while you try to do better for yourself, the haters always try to tear you down. It's all good though. Trust me I know: when people who once saw you in a certain light actually witness your transformation,, inside and out, the hating will begin. A lot of people won't want you to change because of their own agendas.
Your boyfriend might like you feeling insecure about your body, because in that state he assumes you'll stay with him, no matter what he says or does. Even so called friends and family might start hating on you now that you've started exercising and are more confident...especially if they aren't doing anything for themselves and don't feel good about themselves. They're used to the "old" you. But guess what? That's not you anymore. You're a new YOU with a new mind working on your new body.
Regardless of who can't stand the new and changed you, don't worry. Some people have a preconceived idea of who you are and what your place should be, and it can intimidate them to see your story changing right in front of them. It makes them question themselves and where they will fit in your life. Your change forces them to look at themselves, and they may not be ready for that. In turn, they may try to sabotage you, perhaps without even realizing what they're doing. So beware! Stay in control and don't buy into what they say, especially if they try to stick old labels on you. Remember, they didn't create you so they sure can't define you. It's up to you to define yourself, and part of that is not buying into how other people define you.
You CAN NOT take care of others until you get yourself straight, which should motivate you to commit to improving yourself. It's up to you to find the reasons closest to your heart that will keep you on the path and get you there as quickly as possible. Lead by example. Walk the walk.