Yes it's such a rollercoaster - I've been through it with an older hamster but so sad when they are young. You must really miss her, but you need to focus on the happy time she had with you and how she had a home and an owner who wanted her, rather than spending six months in a pet shop and then dying of wet tail.
I agree that there must have been some problem for her to get wet tail.
It helps when you've had some kind of burial or memorial for your hammy and can say goodbye and move on properly.
These may help at the moment xxx
Pet loss - where to find help, tips and comfort on the loss of a pet.
The Rainbow Bridge