I really can't add anything that hasn't already been said, but I wanted to thank the OP for posting this, as it pretty much mirrors some of my fears. I have two boys, a 2 month old and a 19 month old, and often share the OP'S issues.

Our oldest is kind of "my little man", but it seems like I can't do anything right for the youngest (he knows who has the teet). All I can add is patience, and always put your wife and kids needs ahead of yours and check yourself from time to time, to make sure you are doing so, as it's easy to slip.