Don't be so hard on yourself mate, you have come such a long way and hell, you've done it since having kids!! How many mums use the excuse "Oh, I don't have time to go to the gym or do exercise at home". But are you using that excuse and not getting off your bum and losing weight like them? No! You have already lost so much weight and you're making efforts to keep that going by joining the gym! I think you'll find that if you go to the gym regularly your body fat % will drop down a surprising amount! Just think of what your body fat % would have been when you were 98 kilos!!
You've already cut your risk of developing diabetes, having a stroke, getting heart disease etc etc by so much, and I think that's worth more than a number on the scales
Be proud of what you have achieved, and know that you have it in you to go the rest of the way