The conventional wisdom states that high reps with lower weights will improve endurance and muscle shaping whereas lower reps with higher reps will increase bulk.
Each will improve strength.
My experience is that exercise and weight loss are not connected in any way. I would gain or lose regardless of whether I was working out or not.
That being said, I love going to the gym....It eases tension, helps eliminate pain especially lower back pain, and it's just great to look and feel solid.
I applaud your continued workouts. It's all about feeling and looking better anyway right?