I'm in between a 7-7.5 in women's shoes, and my skates are Eastons in 4EE. If that helps. What's your women's shoe size? EDIT: Oh, I just saw that you said you are a 7. Then you should definitely be in size 4 rather than 4.5.
Do you have a lace tightener to help you get your skates tight? That might be helpful until you get used to tying them. A lot of it though, is that you just need to build up your ankle-strength as you learn. It will come with practice.
The bonus part about having women's size feet is that skates are a lot cheaper in the junior sizes!