"He is a quiet gentle man, and affectionate too. But he has had multiple affairs, gaslighted me, controlled finances, never helped with dc which has left me burnt out. Gives me silent treatment if I go out with friends. Puts me down sometimes. Has called me lazy. Puts all his hobbies before me."
Dear OP - please read the above paragraph back to yourself. Your H may be quiet, but he is not gentle. I think you equate being gentle with a lack of physical violence. But in fact he has been emotionally and psychologically violent to you both by action (having affairs, controlling finances, putting you down, giving you the silent treatment when you go out with friends) and by omission since he has been neglectful of you and his DCs (neglect is a violent act of omission).
That is not how a good husband and father behaves. That's how a bad husband and father behaves. He says he will change now that he's lost his cushy number but that behaviour you describe - that's the true man. And he's been like that for years and years. And he thought that was okay.
My DH and I get really pissed off with each other sometimes and have the occasional really big row. That's the full extent of it. He has always been very actively engaged in childcare, put me and DCs front and centre of his social activities, been completely open and sharing with his finances. He's been very supportive of my career. He's been happy for me to go out with friends and wouldn't dream of sulking because I had done so. That's how a decent partner behaves.
Honestly, what you're describing is so bad. Of course there are some good bits - no-one would tolerate being treated like sh1t all the time and abusers know how to love bomb like there's no tomorrow. Indeed, they're usually happy to treat their partner like a princess as long as she does exactly what he tells her to do and makes no demands of her own. It's part of training her to meet his needs.
Please spend some serious time on your own. You need to find yourself again and understand just how strong and competent you are. You're viewing your relationship through rose-tinted glasses because you are scared of going it alone. But you absolutely can and will manage. If your H is willing to wait it out during this time (and I mean several months/even a year), and do some serious work on himself as to why he was willing to treat you so badly and prove time and again that he has changed, then maybe in a year or two from now - just maybe you will feel able to go back. But you've taken such a big step now and you're getting through the hardest part - don't waste all this effort and work.