Firstly big hugs, really sorry to hear that. Secondly I think you can stop the funeral arrangements for the moment as you DO NOT have cancer! And yes I was shouting that !!
CIN 3 admittedly is the worst kind of dyskaryosis that you can have but it isn't cancer. Approximately 1.8% of CIN3 will invade to become cancer per year, or 36% over a 20year period (that means that 20 years later almost 2/3rds of people with CIN3 still won't have developed cancer). CIN just means it has the potential to become an invasive malignancy but CIN by definition does not have any malignant properties. The fact that yours has been detected means that it can be treated, the abnormal epithelium removed and so all goes back to normal.
It sucks a lot, not least because it means that you are going to need regular check ups and no-one likes exposing their bits. But it most certainly is not a death sentence providing you have treatment. I really really want to stress that you do not have cancer.
What will happen next is that you are referred on for colposcopy. Normally a gynaecologist does this although some GPs with a special interest in this also do them. Colposcopy is a bit like a smear but usually they have a special chair so your legs are on stirrup rests. The scope itself is basically the normal speculum they use for a smear but it has a special camera attached so that it's a bit like a microscope and will put a picture of your cervix onto a screen so the doctor can get a really good look at it. Then he or she will swab your cervix with vinegar (yes really) as this turns any abnormal proteins in your cells white (the abnormal cells are not visible to the naked eye). There are a variety of ways to remove the abnormal cells and your doctor will probably explain which method they are going to use to you first. They will give a local anaesthetic into your cervix which will hurt a little bit but won't be too bad, then the abnormal area will be removed. The doctor will probably put some antiseptic cream on a tampon but then tell you not to use tampons until the spotting finishes which may take a week or two. The tissue taken away then gets sent to histology and they check they have got it (the dyskaryosis) all out. After the all clear on this you will need regular smears for a minimum of 5 years but different areas have different protocols.
I hope this helps, I'll watch this thread so please feel free to ask any more questions if I haven't explained anything very well. If it helps at all I have CIN1 and I'm totally chilled about it, although admittedly CIN 1 can revert to normal and CIN3 won't. Professionally the worst cases that I have seen have been people WITH symptoms (usually bleeding between periods or after sex) that have complete denial for whatever reason. You have had a problem detected and so long as you take action, and have the follow up, you're kids are still going to have to worry about who looks afer you / chooses the nursing home for you!!
Lots of hugs and best wishes
Julia x