Sit down alone, just you and not him (yet), no kids around to distract you, and think hard:
Was he always a little like this, and it worsened? Has he been growing cooler since the kids were born? Does he seem ill at ease with the kids and all kids generally?
Was he not like this at all, and there was a point (or a series of points) where it seemed to begin, so this is actually a big change?
If this is a change in his behaviors, what else in his life changed at around the time you realize he started acting this way? (The kids got older and started needing more time/attention? He had a job issue, job change, job dissatisfaction that he might be dealing with by retreating from everything? You bought a new house or moved etc. and there were suddenly a lot more expenses? His parents or siblings had health or money or other issues that affect him emotionally, or he's been asked to help them out/give them money? A friend of his died, or left the area, or whatever? Try to think about changes NOT related to you or sex, and realize that sometimes men act out toward their wives/kids/domestic life when they actually are angry or frustrated over other things.)
Don't let this drive you to divorce without first seriously trying to identify what changed and when, then talking to him. He may deny there is any problem or change and may try to say YOU are seeing problems where there are none. But if one person in a couple perceives a problem, there is a problem, period. Have appointments lined up before you talk to him -- individual and couples therapy, possibly not simultaneously. And you need to ID the changes then talk to him as you've "talked" to us here, but be prepared to stay calm if he denies and deflects.
My first instinct if my own DH were having similar issues would be to worry that something was wrong with him that he wasn't sharing with me. I would not assume he hated me or disliked the kids or was having an affair; I'd first think, is he trying to spare me from something going badly at work, or is his family having issues he won't share, or is there a physical issue (low testosterone or thyroid can both create emotional and sexual issues). Approach this as "I'm concerned about you because I love you, and we need to work as a team because this is affecting how I see you and our marriage."