You have been through a lot but instead of falling apart and gaining more weight you have made a decision to change your life for the better- GOOD ON YOU. It can be hard making time for yourself when your a single mum- I am a single mum with an 19mth old- but it is well worth it when you can go out and have a really good run around with the little ones who I am sure are very active at that age.
As for the revenge- Thats secretly been one of my reasons, if my ex shows up I want to show him what he missed out on
Then happily turn my back on him.
You have 2 very good reasons to lose weight but remember your the most important reason for this lifestyle change. Be stong and you will achieve anything you desire.
I hope to hear more about your progress as time goes on.