It sounds like you're in a pretty tough place right now, but try not to let it get to you. I know it's easy to say, but honestly, you'll feel so much worse if you just give up for a week and then find yourself at 81kgs instead of closer to 79kgs! I'm not sure what your original weight was, but I'm sure you have done well on your journey so far so keep going!
You should also perhaps consider talking to your doctor about some of the effects you're having as a result of being on the pill, there are so many different kinds and perhaps a different one would be more suitable and give you less side effects? Something to consider anyway.
Well I hope you get it all together soon, and I look forward to seeing you back here