Simple - don't let them do it. They are both old enough to understand the concept of not interrupting. Tell them that they have to say, "excuse me", or they will not be answered. Teach them that when you are talking, that interrupting you will result in them being ignored and sent into the other room, or sat on the bottom stair (or whatever your version of time out is).

The boys are also old enough to understand that you need mommy time, or mommy and daddy time. This is just a habit that's been reinforced, and likewise, you can reinforce the changes. They can "read" for half an hour before bed for wind-down time, and that gives you and hubby extra time alone together. Their bedtimes can be bumped.

Kudos to you for being such a hands on mom. I am a firm believer that attachment and responding to needs in the early years creates trust and fosters later independence, but you have to have your own identity outside of just being the boys' mother. Cut yourself a break!