['Last year, when  my kids were both at school, I would get lonely at home sometimes.', "I can understand that. It's usually either parents are happy they are out of the house, or sad that they're gone. I'm sorry you feel lonely.", "Most of the time I'm happy and content but occasionally I get lonely."]
I can understand that. Kids have a big presence and their energy creates a void. Hopefully you can find things to take your mind off of it.
When my kids are in school all day I get lonely sometimes.