Feeling rather low

Life is a very funny thing, as I have often reflected. I am feeling rather down at the moment and I hate it. I hate to feel like I am worthless, like I don't matter, and as much as I try and give myself a good stern talking to, at times it just doesn't work.
I am feeling this way due to a number of factors. I am sure there are some that even I am unaware of at this point in time and luckily for me really, because how much could I cope with at once? (actually I think I have coped with a hell of a lot more)
So why?
Tomorrow is my 13th wedding anniversary.(17 years together) I know that really I only made 11 and a half, not even 12, although this time last year I still truely believed that we were going to work it out.... I digress..... so yes I guess I remembering all the times, good and bad.
What do I really miss?
I miss the connection with a single other person. I miss the ease at which my life had. I miss the belief that I had a life plan. I mean I didn't know exactly where I was headed but knew the general direction. I miss the life I had, the fact that I had my kids all the time, (and yes it is every mothers dream to have a little alone time, but when you have no choice, when you can't see them, it is physically painful) I miss that we had shared experiences, I mean I had only known him my whole adult life.
It is so hard to remove yourself from those experiences, those feelings, those memories.
So here I sit in our house, the home we shared, where our children were conceived and our lives mapped out. Here I sit alone,and lonely. This will be my last anniversary, next year I will be divorced.
So I sit and ponder at what life might have been, but I am honestly trying to think that maybe,just maybe there are better things to come. That maybe the universe has other plans, and that maybe,just maybe life will once again have a plan, a meaning and a direction.