Fluctuating weight, what do I do!?!

I would say I am about 5"3 and I weigh 196,  last summer I got down to 145 after a hard time I was dealing with and loved my body and I let myself get in my comfort zone afterwards leading me to gaining weight badly... Now I am trying to shed pounds and it's been really hard, I only eat once or twice a day, that's the normal for me now I am not starving myself, and my weight just seems to go up and down. I do admit that I do not eat healthy and I drink sodas like it's going out of style, but when I got down to 145, it was like the weight just fell off my body and I was eating this exact same way that I am currently but it just isn't cutting it now, any tips on losing the weight without cutting sodas out from my life?? & I do go to the gym as well! I'm also having trouble with motivation so motivation tips would be nice too! My goal is to get to 130-135lbs! Feed back appreciated! 
^145                                  ^196