OP I have been in a very similar situation and completely understand the feelings of apprehension and anxiety, walking on eggshells and worrying about going home to be sulked at.
I left home at 18 after constantly being belittled by my dad, compared to my sister and made to feel like shit, I had rock bottom self esteem and ended up with a man who utilised that to his advantage and treated me like shit. I was so desperate for his love and some affection I cooked, cleaned, ran round after him and fawned over him. I was working 55 hours a week and would walk into a very messy flat, I then had to spend hours tidying and cleaning it and walking the dog (his dog) and was exhausted.
I was younger then him and moved into his flat so it was harder for me to escape, I adored the dog and it became my dog as it preferred me, my ex had a short temper and my ex didn’t hurt the dog but had angry outbursts which scared it.
I would love to tell you I was strong enough to leave him but he dragged me down so much and made me feel like I didn’t deserve anything better, it sounds like you are heading down the same path, it’s easy to get used to people treating you like shit and you forget it isn’t normal. I was lonely as I didn’t want my friends to know what my life was like so I did have some awareness my situation wasn’t good.
In the end my ex cheated and it made me reevaluate everything and gave me the strength to leave, I told my best friend the truth and of course she already knew and had been waiting in the background for me to come to my senses, I went to stay with her and I took the dog.
Your relationship is going nowhere and the longer you stay with this man the more it’ll break you and it’ll be harder to leave, it sounds like he doesn’t love you or want you or the dog and you are happy with the dog, you just need some courage now.
Get the barrel of your lock changed so you don’t have to ask for your key back, it’s easy to do yourself if you find a video online. Can you stay anywhere else for a while to avoid him? This means you won’t give in if he tries to get you back, I’d even pay for a hotel or B&B if it means you’ll feel safer, it won’t be easy to just break up with him, you are useful to him with looking after the dog, the use of your flat and he probably gets off on putting you down.
Be honest with family and friends for support and so you won’t change your mind, don’t try to break up face to face but send an email so you have a copy and he can’t twist things. Put in detail the reasons you want to break up (he can delete a text) then if he harasses you afterwards you have that as insurance and proof of why you left. Keep any text messages where he has been unpleasant as well, he won’t want people to know how he treated you and is more likely to back off if he knows he might be found out.
Try to keep your reasons for breaking up brief but firm and don’t make it easy for him to beg for another chance or promise to change, if he knows you are serious then he will give up quicker, I’d say you no longer love him, most men know that your love is their key to control you. If you keep it friendly as well then he has no reason to start an argument, just write as little as possible whilst getting the message across write it as if you didn’t want to waste words and it’s just a courtesy to him because your mind is made up.
My life was so much better really quickly when I left my ex, it was hard to start with as I thought I missed him but I just didn’t know any better, I soon relished the freedom and peace that comes from not having to please and appease someone else constantly. I was so used to not being able to think for myself that it was liberating and the dog was much happier too. We got another little flat and I took pride in making it a safe clean tidy haven.
It’s no wonder you are struggling keeping on top of keeping things clean and tidy with another person making a mess and then criticising you, you are stuck in a cycle with working as well and will be mentally and physically burnt out, a dog makes extra mess too, if you dump this prick you will likely have the strength to get tidy and organised.
This is long sorry but just one final thing: please keep the dog! Not just for the dogs sake but it sounds like you need the unconditional love, it’ll help make you feel safe and give you an incentive to go out when you feel low, you said you are making friends due to meeting new people too.
You can do this and turn things around and be happy, it’s so scary to take such a big step but I promise if you do you’ll be much happier. Don’t get into another relationship until you work on your self esteem issues, I had therapy that helped.
You deserve to be treated with love, respect and kindness but you need to love yourself first. Act as soon as you can now you have been brave enough to post here and have the validation from so many people 💕.