I think you need a (caring and well meant) kick up the bum to be honest.
You've said you want to be loved by this man, but that option just isn't available. It's a form of masochism to keep wanting to achieve the impossible, so what needs unlocking in my view is: Why are you doing this? What are you afraid of, if you do something different?
Your husband is a selfish man and your sons are following his example. You're coming across like a doormat who quite literally cleans up others' shit.
Your husband could tell you he loved you from morning till night, but what would that prove? Nothing, because he doesn't mean it.
As this thread has gone on and posters have reacted to your disclosures about your husband's selfishness and entitlement (and your behaviour that enables it) you have rushed to defend him and put the blame on yourself.
I bet you've had other threads that have gone like this about this situation, if it's been going on for three years. Did they all go the same way?
The answer to this is in your hands and Lord alone knows, you need to stop vacillating and make a decision one way or the other. Either get help and get out or stay and remain this unhappy, until he finds someone else and takes the decision out of your hands. Because there is no other option, with this man and this relationship.