Don't know if my story will help, but here goes.
I was married for 19 years when I found evidence of what I believed to be his third affair (and what I later confirmed to be his fourth or more). Kicked him out pronto--I had had it with his philandering, blameshifting, deceptive and NPD ways (he is a diagnosed narcissist).
Started dating WAAAAAY too early (I recommend taking a long time to get used to being single) and had the predictable results. Be prepared--that first post separation/divorce relationship ending can be VERY rough.
FINALLY divorced nearly 4 years after the last D-day (divorcing a narcissist is its own circle of hell), got a very good settlement and continued to adjust to singlehood, having a couple more relationships that didn't work out, etc. It's par for the course--I don't regret a lot of it because I really learned a lot about myself.
Probably the BEST thing I did for myself was to audition for (and be accepted into) a professional chorale. I have a musical bent and had been singing since I was very small. I studied voice (and other instruments) off and on, but this gave me a huge focus that was all MINE! Ten years later and I am STILL singing with them and LOVING every minute of it. My group really helped me get my feet under me and gave me a purpose and a mission outside of my career and my kids. It was good for my kids to see me energized and excited about something like this, and they were (and still are) very supportive. In fact, my oldest sang with us for a season.
So, about three years ago, I pondered answering a personals ad on Chemistry.com. He seemed to be too athletic for me (I'm not a couch potato, but he is an avid bicyclist). But I decided what the hell and reached out to him.
We have been a couple ever since. Happy as the day is long, content, not living together (we each enjoy our independence and autonomy) but a couple.
We vacation together, go on weekend trips, go antiquing, salvage yard hunting, attend concerts and just hang out together. We are happily in love and very content with the way things are.
We are 51 and 62.
My advice (for what it is worth):
Don't get too wrapped around the axle about coupling up. Get healthy, find something that works for you that is healthy (like my singing) and socialize in groups and with other like-minded singles.
Don't compare yourself to the ex. They are on their own broken and rocky path.
Cherish the time with your kids, but also pamper yourself when they are not with you.
Learn to be content with your own company and to be happy in solitude. When we attach out of neediness or loneliness, we make very bad decisions.
My SO (fondly named Garage Door Man or GDM) attended a series of meetings at a local hospital designed for "men in transition." They emphasized things like not delving into work as an escape (which is exactly what GDM did), not using alcohol or drugs as an escape (fortunately not a problem for him) seeking balance, and not dating for a year. He followed all of that advice (for the most part) and was rewarded (?) with me.
IC is helpful and recommended.
Oh, and you will enjoy the story of what happened to my ex. It's a good one.
My ex ended up with the OW, at least for a time. He moved into her house and financed its renovation. He bought her an expensive automobile. She didn't like sailing, so he bought an expensive motoryacht. I think she had a pretty intimate relationship with his checkbook.
Anyway, he came into a sizable inheritance and bought a house and moved them all into this house (she had two kids--both under 5 when she started the affair--she's a keeper to be sure).
She had a brother who is a convicted felon and a meth addict. Apparently, my ex felt like playing Mr. Generous and had him as a houseguest (around my kids--yikes!).
Right around the time they split up, the ex's identity was "stolen." When he was finally caught by the police in Arizona (we live in New England) he had my identity and that of my two children. I feel strongly that the OW (TwatWaffle) had given her brother all of this information.
So now my ex had to give up the big house, moved to another house (he has moved 5 times in 10 years--stability anyone?), the expensive 38' motoryacht blew an engine and is not operable (but he still has to pay a sizeable note on it monthly, as well as storage fees and insurance, he has no girlfriend (told the last girlfriend the trust about what happened in the marriage and she skated, lost his job last year and, oh, darn, has to pay a sizeable chunk to his ex-wife in alimony.
Karma came and came and came.
But when it finally did come . . . I had stopped waiting for it.
Cat