Just have to add another reply of support.
There's nothing selfish about maintaining your health. If an hour and a half is what you have to do to achieve your goals, then do it. I also am a mother of a two-year-old and work out at least one hour six days a week, sometimes I'm able to add a 90-minute workout here and there. It may seem now like you're not spending time with them, but in the long term it will be for the best. You don't want to wait until the kids don't need you anymore to find that you have all sorts of health problems that will drain you not only of time with your children but of finances, emotional stress, etc.
My father-in-law died last year of diabetic complications...and I saw first hand how devastating it was for his family. That was what really got me off my butt and working out.
Also, I have found that with consistent exercise, I have more strength and energy to lug my daughter's stroller around town so that we can go to playgroups and shopping, etc. I'm more patient with her because I'm less stressed. I'm happier because I'm no longer overweight; thus, more cheerful around her. The quality of your time together may be more important than the quantity of the time.
I also agree that these people are sabotaging you. Having lost 30 pounds this last year, I've had all kinds of interesting comments, both positive and negative, from people. My husband has been so inspired that he wants to exercise too. And on the other hand, I often have co-workers practically trying to force feed me doughnuts. Just keep your eye on your own goals and don't let these people drag you down with them. It's a lot easier for people to criticize successful people for whatever reasons they can cook up than to be successful themselves.
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