Liz,
Sounds like you are in the "honeymoon" period of the break up.
Wait until he starts seeing the accounts being moved and noticing no FB pix. Things could get a little meaner. He thinks that you "need" him to survive and to accomplish what life has to offer.... um... NO!!
I would keep in contact with mom and tell the girls then that you are not leaving their lives, that you are around, just not everyday, and big "brother" is too. You can take them for ice cream anytime.
Be careful with him. Sounds like he could be a stalker type man. He's in complete denial of what is happening. Why would you want to see his vacation pix when you were supposed to have gone on the trip. Really weird. Be smart and always watch your surroundings. Don't ever let your guard down, watch for his car at all times. Double check with your phone company that you are no longer on the "gps" find the phone app. You just don't want to be naive to what he could have done/do.
Sending big hugs and stay safe. The next chapter in your life is just about to start!!