How to remain motivated? How to lose weight?

I have no support. I'm not complaining, but it's difficult to remain motivated when you have no one to keep you going. Whether you fail or not, it's only yourself your damaging. And if you're like me, you really don't care. I want to care, but I don't... at least not enough. Here's the catch: I'd like to lose 50lbs. I'm a medium-framed female, 5'7", 180lbs approx. Eating healthy isn't the issue. I can control myself there... when I care to. I don't eat dairy - dairy is miserable for you. Look it up if you don't believe me. Example diet plan - no dairy please? Simple exercise plan? I can get access to a gym, but it won't be for about two months. I have a 10lb weight and two 5lb weights. I can't exercise outside, I get heat sickness VERY easily. I'm not just complaining - I literally puke and break out in rashes. Once I get on this plan, how can I remain motivated to keep going. I really want to for my health mostly. I have no confidence issues.:) Sex would be nice for exercise, but I'm not getting that right now... SO. Help? I want to start ASAP, but I don't want to if I know it will just fail. It does every time.