Thinking of ending or taking a relationship break

I've been thinking alot about my 7 year relationship. I've been unhappy for a while now. We fight over fighting how stupid. He makes it seem like it's all me but then apologizes and says its him I need space we r together almost 24/7 hes a disabled vet and I'm a stay at home mom. When he ask me why I'm still with him that's a normal question for him to ask me. I tell him cuz I love him and he loves his daughter other then that I dont know y I feel like I will be happy single. I'm possibly thinking if ending it or taking a break but I dont know how to start the conversation which wont go well it probably end in yelling n crying on his part. I feel like a coward n wanna write him a note explaining everything. I dont do well confrontation n I definitely dont wanna cause the heart break. But I literally feel like my soul n who I am is disappearing

Help what should I do how do i start of the conversation. I want my daughter to have both her parents but also want her to have happy parents. Plz plz give me advice