You don't have to be. You can lose weight and even if you don't have support at home, there is plenty of support here on SparkPeople.
First, please stop the negative talk with yourself. It doesn't help anyone that you are talking so badly of yourself. Would you say that to a friend? Not likely. And you shouldn't say it to yourself. I know it can be difficult to stop the negative thoughts and self-talk, I've been there before too, but you can get through this! Here are some articles about stopping this way of thinking that you may find helpful: www.sparkpeople.com/resource/wellness_arti
If you haven't yet, please take some time and check out some of the SparkTeams on here. There are plenty of teams on here that I'm sure there are at least 1 or 2 that you may find interesting and can give you a great support system. The message boards are another great place for support, but the teams are where you can go to chat with other like-minded members that can offer advice.
You are not alone in this, so please remember that -- and be kind to yourself!