Struggling with Weight Gain During Chemo

Hello everyone, I'm very new to this site and I think I'm going to like it. So, I've been diagnosed with stage 2 colon cancer, had 18" of my colon removed, no bag thank goodness and just finished up 6 months of chemo. Before chemo started, I lost a lot of weight because I was filling up with fluids from being in congestive heart failure. Long story short , I lost a lot of blood and that put me into congestive heart failure but the loss of blood was because of a tumor on my colon. Anyhow I'm very upset that I gained the weight back and I know it's from being on chemo because my diet is less and I'm also a type 2 diabetic so I really have to watch everything I put in my mouth. I know eventually I'm going to lose this weight but it is very discouraging that I was doing so well and then gained all of it back. Just thought if anyone else went through this with the chemo and the weight gain. My oncologist hasn't brought up the weight gain which I'm surprised because every time I go to an appointment every 2 to 3 weeks I'm 5 lbs heavier. I don't want to bring it up because I know it will upset me. I'm hoping now that chemo has ended that I won't be gaining more weight back, but now I have to start all over again. thanks for letting me vent.