Trying to gain weight after an illness and sugery

Hi everyone! My name is Mel - I'm 28 and living in the suburbs of Detroit, MI. My story is on my journal (feel free to read), but I'll share it in a nutshell here. Basically, I was diagnosed with ulcerative colitis (an IBD) which caused me to lose over 30 lbs this past spring. I had surgery to remove my large intestines in May, and that caused me to lose even more weight. I am 5' 6" and I bottomed out at about 86 lbs after surgery. I am currently maintaining 100 lbs, and have been maintaining this weight for the last month. Maintaining is better than losing, at leasts. But I need to get back to my normal/healthy weight of 125 before my next surgery can be scheduled (I have two more surgeries to go). I really want to have my next surgery in January, so I NEED to hit my goal weight by December.

I used to use this site to count my calories and maintain my healthy weight. I left for a while though because it became an obsession. But now that I need to reach a goal, I came back to see what I need to do. So here I am!