I identify with what you're saying about somehow feeling a little like you're "betraying" your Mom, even though you know rationally that it's not the case. I think it's smart that you realize that this is a sensitive area, because it will continue to be so during therapy, especially if and when you choose to talk to your mom about the past.
Yes, others had it a lot worse during childhood. That's absolutely true. I often fall into this thinking trap. I had a very loving, but dominant father who would say "I'll give you something to cry about!" and I fall into the trap sometimes of thinking that the universe is out there saying that too. But the universe only wants good for us, and healing. But we only heal when we pay attention to it. If we ignore it, it doesn't get better, whether it's a broken leg or a broken psyche.
It may help you to always remember what you are grateful for, even while you are working through the things that caused you pain. It's all about keeping perspective. If you become a whole, complete person without this pain, you will live a happier life and you will extend that happiness to others you love -- including your mom. You will behave differently toward your own husband and children, if you have them. Most of all, you will be able to take some of the burdens you carry and set them down. The first time this happens, you will be amazed at how it actually feels as though you have set something down physically. You will feel pounds lighter when you can set something to the side with understanding and compassion.
You're in such a good place for this work, Steph. Thanks for writing back.