Guilt on missing out, how do we deal with it?

I just missed out on a 40th wedding anniversay our kids planned for us, by the time we got there I was shaking so bad and feeling nauceous, room spinning, I spent the entire time laying down in the car. I felt so guilty. I am the queen of guilt, raised very Catholic, so I can feel guilty about anything. My parents instilled a great sense of guilt in me. (PS - I'm still Catholic, just a little more forgiving). I just feel so bad missing out on major milestones, and right now my daughter is cleaning the house for me. Some family members get it, some don't. Any advice for dealing with guilt?