Could you be a little depressed? SAHMIng to one is hard. In most ways, I actually found it easier with two (note that my kids are 4 years apart, though). It's a bit of an echo chamber.

Do you have a group of mom friends? I desperately needed adult conversation during the early years.

Teaching kids to play independently is a lot of work, but worth it. My son was just very ill and got a lot of attention as a result. He now is used to it and is constantly asking to be played with round the clock. It's exhausting. He is the same child as he always was, so I can clearly see that we "de-trained" him. From babyhood on, I have always tried to melt away as soon as I see them playing happily without me. I reinforce it, too ("Thanks for letting me get this work done! Now let's read a book for a while," and then later, "I need to do XYZ and then we can...") Also, teaching children to wait is a huge life skill. I don't mean to sound like a hopeless prig, but I do know a lot of AP-minded parents who have always pretty much dropped everything for their child. It sets up an expectation for the kid that they are always #1.