Weight loss being Breast cancer survivor

I gained 40 lbs with Breast Cancer with Chemotherapy and Radiation. I am currently on oral Chemotherapy and still maintaining that same larger weight. I haven't had an appetite since starting Cancer Treatment. I still do not have an appetite but have to force myself to eat. I was told that I need to increase my calories to 1500 to get my metabolism working again but it is at a standstill. This scares me too, but I still do not have an appetite. I drink the protein shakes often to make sure I am getting something in. I need to lose weight so I am commenting on your post to find out more. In the past I took hormones and Adipex and lost weight quickly but now that I have had Stage 2 Breast Cancer, I cannot do that diet again. I appreciate any information that you can give me. My daughter is getting married in November, hoping to lose a few pounds plus by that time. Thank you and God Bless, Jill