Those cats are funny aren't they. 
Hello meandmyfour. We must have been going through it all at the same time. I finished rads in December too. Also had mastectomy and chemo and am on Tamoxifen now.
What you describe totally chimes. I know it's kind of obvious, but I concentrated so hard on getting through treatment that I hadn't thought through how to cope with living once it was all over iyswim.
My BCN described the time immediately after treatment as one of shock and reflection. Without the slog of treatment you have space to realise what you've been through, and part of that is obviously the fear of recurrence. She said for some women it's akin to Post Traumatic Stress, which I thought a bit ott at first, but then when she listed the things we've been through, so operations, bits of body lopped off (!), poisoned, burnt, even the trauma of hair loss, which let's face it isn't easy..! Well maybe she has a point.
Kurri's right (I hope!), so am trusting that with time it'll get easier. Also, am guessing you're probably still knackered like me and getting used to the Tamoxifen (I'm not having Herceptin) takes a while. I have more energy week by week, but still feel quite achey and irritable too some days.
Swimming's been good for me both physically and mentally. I know a lot of people on here do yoga, so I might try that. I doubt you've got much time with 4 kids - I only have one, so I totally take my hat off to you. How on earth do you do cancer treatment alone with 4?! How old are they all?
Another thing that's helped me is very good friends - BF in particular, who has been there every step of the way and still is. I often talk to her in a way that I can't to my DH. Something about a woman's intuition I think.
This thread is really brilliant too. Just knowing everyone on here has been through something similar. We all have the same fears of recurrence, and there's definitely strength in connecting with others who get it. I've found that ever so useful. Why not come here and talk to us a bit more? If nothing else, we can distract you.
Blimey, I don't half go on. Better get some work done.
For those
yesterday by my hospital not having heard of mammograms, you'll be relieved to know they have decided they do know what they are and I can have one. Hooray for medical science. 
LGF. Hope that headache went and you're okay today. What day are you on? Should be rising back to feeling alright again soon.
Sparkle, good luck with your appointment later. Will have fingers crossed for you. Put a bottle to chill. 
Hope all others are good today.