I'll share what worked for me, and I hope in just responding, I'll give you further encouragement.
RE: Children. Yes, they get a choice in where to live. And I respect that. I just pray that this apartment is a place of peace, where they can share their feelings without being challenged, where prayer at least once at night to tune into God is expected (whether they participate or not), and a place they can 'just be themselves' or hang out. We can't push as hard on faith and morals, and their other parent may not reinforce the values we want to instill. But we can still expect some chores to be done, and teach them life skills (cooking together, shopping together, ...) And we can ask them questions about why they choose what they do, and share what God's Word says about it, positive or negative. That way they won't think it is you, if the news is negative. I shifted from more 'telling' to more just waiting for the right moments in visits. Case in point: With Prom right around the corner, I was honored to be asked to look for Prom dresses with my 17 yr old. It gave me a time to share about modesty, and its importance, and share what it looks like from a man's perspective of a lady not well clothed, and would she want that. Asking them, would you like my advise or perspective? And really listening more too. In the end, They just want to be loved. I give them a hug and blessing each night.
The past: Whatever mistakes, or poor roads traveled, they are past. If need be, confession. Then look up. I like to ask God in the morning: Today is a white canvas, what are we going to paint on it today? And I ask what I might face and to be sensitive to others. And I find God sends people at random.
The future: my motto is 'the whole world changes in 24 hrs'. it's OK to plan, wish, dream. But life can change so-o-o fast: Gall bladder trouble and surgery, and a year to recover. Never thought I'd travel much, and last summer, since I let some daughters do all the planning and I just paid the bill, I had the most pleasant trip to Glacier National Park with all its majestic beauty. Suddenly one son gets a job with his brother, and is moving in 3 weeks, and he hasn't finished his trailer home, so I'm building with him every day I can now. One day the marriage is the best in the world, and now its finished, legally and spiritually. The bottom line: I expect change, and to be open to what God has in store, both the cross and the resurrections, each day.
The present: I give thanks and try to recall all the good things God has done for me many nights, even if it was just the energy to get through the day. Pretty sunsets; the stranger at work that smiled and actually noticed me and said Hi; the car not breaking down; employment. And I try to offer the challenges of the day up for those who have difficult crosses, like the divorced, widowed, or children without parents. Then things don't look so bad, and my suffering has helped someone.
Sorry for the long story. Hope it helps.
You just asking the question how to start over, implies you are ready to move forward. And that is a big step itself.