Breastfeeding mama looking to lose weight

I've been on and off this site for years. I had a baby girl 9 months ago and actually lost weight during my pregnancy and am 15 lbs lighter than before I got pregnant. BUT I still need to lose another 40 lb at least. That would be a manageable weight for me, if I could just get there. I am still breastfeeding and not planning to stop for another 3 months at least. I need buddies to help keep me going. I am also a night shift nurse who works one week on, one week off, so exercise is an issue. I am planning on using our neighbor's pool once he has it going, but that's still a few weeks out.