I think you need to reassess your goals and be more realistic.
"I did expect to have dropped at least 15-18 pounds and I am at less that half that." In two months, that would be a weekly weight loss of nearly 2 pounds a week. Perhaps when you needed to lose 115 pounds, you may hit 2 pounds a week. However, you have less weight to lose now, even with your setback.
With a loss of 9 pounds in 8 weeks, that's a little more than 1 pound a week. That is very steady, consistent loss. It also is within the range of what is to be expected. You are doing nothing wrong. You are losing less because you have less to lose. You have been getting results.
Also, make sure you track non-scale goals like measurements, body fat and fitness performance. That will give you a more complete picture. And, as you get closer to your goal, you may not lose any weight at all, but these numbers will be another way you can measure your progress.
Just hang in there and celebrate the success your are seeing, not beat yourself up over what you want to see. You can do it!