My sister had ovarian cancer at the age of 12 back in 1969, so her treatments were very invasive and rather experimental. She had struggles as an adult dealing with all she had been through. I don't think that is particularly unusual. Have you considered therapy?

The forgetfulness may actually be related to chemo. This same sister had breast cancer, went through chemo for that, then ended up having a bone marrow transplant and more chemo. She had very severe short term memory loss (yours doesn't sound anywhere near that bad though). They did say the chemo might have been the cause of the memory issues, so you might want to ask about it. Can't hurt to ask. Or, it could just be anxiety related, which again might indicate the need for some therapy.

I would suspect you could find a survivor's group in your area also. Being able to talk to other people who have your common experience might be really helpful. Check with your hospital or oncologist. They probably know how to get you in touch with the right people. The American Cancer Society might also be a good source.