Wow. Everything you said rings so true with me. It's nearly seven years since I was diagnosed, but I still think about cancer every day. Maybe I should give myself a day off!
Certainly the emotional effects of cancer and survivorship have taken me by surprise. It's very easy to allow the emotional effects of having had cancer, and the fear of it returning to take over your life. At times it has taken my life over.
In a way, I'm not sure what advice to give. On one hand I want to say "keep yourself busy and don't let yourself dwell on things", on the other I want to say "you've been through a great deal - give yourself time to reflect and come to terms with things".
Personally, I spent about a year after I'd finished treatment just continuing as before - same job, etc. Then, after a while, I looked at things and decided to change some of it. That's when I went to university to get my degree and my master's. Of course, your situation is different; you've finished your studies (well done!), but I'm betting that in time you'll reflect on things and, whilst some parts of your life will stay the same, you'll also end up doing things with other parts of your life that you wouldn't have done before cancer.
Good luck with everything, uscjpa. Loads of us here have made or are making the same adjustments as you - indeed, I'd venture to suggest that for many of us the very fact that we are here reflects a part of that adjustment.
The best thing to do is what you are doing now - keep talking.