Just my 2 cents,
Everything in your dream is a representative/characteristic of self/or feeling.
Your house is your heart, closing the door and walking your dog is you being independent of your ex and your dog is your buddy, a trustful companion who
gives unconditional love.
Calling upon your ex brought confusion, fear, anxiety, and in the end you were'nt
sure what was real. Except the pain, that you felt in your soul.
Right now your emotions are raw and you need to be able trust yourself again.
Take some time to grieve the loss of the relationship and remember what caused the breakup and heal. Do things that reinforce who you are. Impower yourself by being self sufficient.
H.