Loislane2010 it sounds like you guys are just disconnected at the moment. When was the last time you made time for each other? Get a sitter and spend some time just the two of you so you can reconnect and remember why you fell in love in the first place.
Maybe DH is having a stressful time at work and is taking it out on you.?
If all else fails let him try being a SAHD and see how long he can cope.
And you are definitely not a failure, I'm sure your kids think you are amazing.