How do you find the courage to leave

How do you find the courage to leave?
My partner and I have been together for just over 8 years, we have 2 kids under 6. We both work. The House is technically “his” as he bought it before we got together and it’s all in his name.
Things have not been how they should for a very long time. I am not in love with him
And haven’t been for a very long time. He knows this. We have had a conversation that went back and forth of how neither of us knows what to do. I think he was waiting for me to say I’m done but I just couldn’t. I am not attracted to him there is no intimacy and it’s starting to feel like everything he does Irritates me. I feel like apart from the kids we have nothing in common.
We recently went on a “date night” first in years and it just felt awkward.
I don’t remember the last time I felt happy. Or enjoyed anything we did or do as a family together . We don’t fight or argue. He has issues with alcohol, and has acknowledged that but doesn’t do anything about it.
I feel like the kids are starting to pick up on the vibes in the house. I’m not showing them how a happy family and how healthy relationships should be. I feel like I deserve better, I deserve to be happy and so do they.
I spend all my days off running around after everyone in the house, doing all the cleaning, laundry, shopping, appointments etc and he cruises out to work and back home when he’s done.
I guess well I actually know I want out. But how? How do you say it, how do you do it?I’m breaking my kids family apart.
Also to add to this I have no one where I am, no family as they are all overseas and basically 1 friend.