feeling hot & cold :/

I feel so irritable towards myself. I go to the gym three times a week and try my best to stay on top of my health, but then I stop caring. I let go of the expectations of my body, but then I get wrapped up in how much I hate my body. I don't understand how quickly I can feel comfortable, but then immediately get disgusted with myself. A few years ago I took action and lost a bunch of weight within a few months and was weighing myself frequently.....and I have craved the idea of doing that again.. but I know it isn't smart. I know my partner would probably be disappointed in me. But currently in that mentality of hating my body and wanting to do anything to get it to be different.