Honestly, it sounds like you are suffering from depression. It might be situational as opposed to chemical or psychological, but the symptoms are the same. You might try talking to a therapist or a doctor to see if there are things you can do that would help improve your mood while you hunt for a new job. That stuff permeates everything you and can drag every single aspect of your life down. Trust me on this, I know from a lifetime of continued experience.
Other than that, the only things I could suggest are to try to make a concerted effort to focus on the good things you have, mainly your daughter and wife. Talk to your wife and let her know how you feel but also let her know how important she is to you so maybe she'll understand a little bit more what you are going through. Take the time to be with your daughter. Even if you're tired, I think you'll find the time with her is more therapeutic than it seems it might be when you're beat.
And get sleep, as much as you can. Stick to an evening rhythm that gets you in bed and turned off for the night so you get some reasonable sleep. Not every night can be like clockwork but the more recuperative sleep you get, the better off you will be when you're awake.