The guest seems pretty angry, but not unreasonably... She seems to address problems she had with you and the property. You are the one who seems to be overreacting and unreasonable with this post.
Let me ask you this, what happened? Tell us your side of things. Did she have hot water at any point in her stay? Did her dog damage the furniture? Do you have pictures to prove (that is an easy one to prove if it actually happened, though not insured by airbnb). Did you offer any compensation for not having water and electricity?
Tell us what you did to try to solve the problem for her.
All hosts here know that problems can occur during a stay, the important bit is what you do to solve them, and how the guest perceives the steps you are taking to try and solve them. If it seems like you don't care or that you are not taking imediate action, the guest can feel cheated. I've had plenty of problems when guests were staying, not one ever complained about it. Let me give you a few examples:
1) Guest messages me at 11pm to say the refrigerator is not working. I tell her I can go over to collect the food she had in it to store, and that I will sort it out first thing in the morning. She said since I was going to sort it out in the morning she would just put everything in the freezer till then. At 8:30am I was at the door with a new refrigerator.
2) The maid was cleanning an apartment for a guest that was to arrive at 3pm. While we were cleaning (about 9am) the maid broke an exposed pipe, water went everywhere. The first thing I did after I turned the water off was send a message to the guest to say what happened, but that we were already sorting out but that might be a delay on her check-in. The key is to always keep the guest informed. Found a plumber who could come asap, went out bought the parts he needed, came back, helped the maid clean while he worked. 3:30 sent a message to the guest apologising again and letting her know the apartment was ready for her.
Those are just a couple of problems I have had. The main thing is to drop everything to sort the problem, and keep in constant communication with the guest to let them know how you are going to sort the problem.