A little help please..

I have OCD, I am a worrier, we have been over all this before. I have been really struggling with worry, fear and anxiety my whole life but it has really been bad the last year. I am still battling trying to find just the right combo of meds that both help and don't have too many side effects, so while still working on that I have decided to really try and tackle the anxiety and worry in other ways. I have really been trying to figure out what exactly causes me to worry and how to stop worrying about those things. Sounds easy but it is not. I have discovered that the number one thing I fear, worry, stress about is getting old and my children getting older and I just don't know how to let go of that issue. I have five kids and I love them all to peices at just the age they are now and each time one of them has a birthday it makes me sad, each time Krews leans something new, gets a month older it makes me sad, becasue I know they will all only be this age once and I know that while the days with five young kids sometimes feel long the years are short. I guess I have focused so much time and attention on being a mommy, on raising kids, that I just have know idea what my life without diapers, breastfeeding and naps will be like. That is scary to me. I LOVE having a baby in the house, I love having toddlers, I love my kids being at home and I hate it when they have to go to school. I am not the mom who can't wait for her kids to grow up and move away. I LOVE being a mom, no matter how stressful it is to a house full of rowdy little kids. I just fear them getting older. I fear change and I just for the life of me don't know how to get over it. I have tried telling myself, it's great this is what they are supposed to do grow and change and I know in my head that is true and I do love watching them at each new stage in life but there is still a part of me that is sad knowing that they are only little for a short while. So tell me do any of you feel this way?? Any of you have any suggestions on how to combat this??? I would love to hear your advise...