Hello Bue_Bird, and a warm welcome to the site.
I am so sorry that you want to separate from your husband but being in a marriage if you are not happy develops feelings of many issues that were not present once before when you were first in love.
We know that our love in a marriage does change over time because remember when you met each other, there was no fear, or if there was, you both coped with it because your love overshadowed everything, he was there with me or she was also there to cope with any situation that came our way and didn't care at all as long as we had one another.
A marriage has to be happy, whether this changes from day to day, depending on the circumstances and whether you both can handle any situation together, but as soon as this goes and don't particularly care, then love may have disappeared, although you don't want anything to happen to your spouse, so then love changes to caring for them, but is this enough to hold a couple together, no, not really, because there are many other physical expectations that are needed to hold the couple together, and this isn't only being intimate, it's laughing together, going to see the kids/grandkids or even buying them a present for their birthday that indicates this.
Your crying will eventually stop once you become settled into a new home, that's exactly what happened to me, and you develop your own life, what pleases you and what you may attempt to do that you couldn't while being married and your personality may also change, showing a different persona, that was once hidden away.
It's how you feel about why you are doing this and if you believe this is exactly what needs to be done, then perhaps it could have been done some time earlier, only you can answer that.
Can I suggest that you do visit your doctor, what they suggest now may be totally different to what they would have several years ago, but please visit them.
The same happened to me and you do meet new friends.
Love to hear back from you.