Gaining weight after big loss

shellcanada71

I am on a spiral I guess I cant say downward its upwards. .I lost 105 pounds it would be 7 years ago and kept it off for like 4 yrs then I had to have major back surgery to remove a tumor in my lower back, I was forbidden to go back to my old work out routine actually a whole 3 weeks I wasn't aloud to do anything and the next 3 months had to slowly exercise so naturally I gain weight, over the next yr I put back on 35 pounds .My back surgery was almost 4 yrs ago and I have been struggling with getting this 35 pounds OFF.. I treadmill 40-60 minutes a day level 4 incline at a 5 or more ..I do speed drills on my tread 2 days a week meaning I crank it up and run till I cannot run anymore..I am lifting weights ..and doing squats..I cannot do sit ups or any exercise involving me laying flat on my back on the floor . I am eating around 1500 to 2000 calories a day..I must admit I do have a sweet tooth but it is manageable .I drink my 8+ glasses of water a day ..I try to do everything that I read and heard is right to do but this darn 35 pound just will not come off?!? and it is getting really depressing.. the only thing that even remotely works is right after my sister passed I had no appetite and ate very little I lost 20 pounds but of course you start eating again and BAMB it come right back plus some I was able to get the plus some off. I do not know what else to do..I am beginning to think alot has to do with the extra skin I am carrying around from my initial weight loss ?