It will take time to figure out what you want to do long term OP but in the meantime can I offer some survival tips? The first is the hardest but it's the key to everything so worth making the effort, you need to detach. Stop allowing him to colour everything with his mood and focus on DC and everything else around you, stop making (because he manipulates you into making) him the centre of everything. It's hard because his moods are so oppressive but it's liberating to realise you don't have to sit under the cloud he creates.
Try to stay calm, don't let him push you into that hyper state where you overcompensate for his silence and sulking. Get on with stuff in your usual way and don't let him stop you, essentially act as though he isn't in a mood. So do your tree this weekend and if he wants to sit in a corner and sulk, let him.
I can't stress enough how important that detachment is though, you know now that this isn't you, reread this thread every time you feel that belief wavering and keep the thought at the front of your mind that this is HIM, you are just going about your daily life. He currently has you dancing like a puppet to appease him, to not upset him, to achieve impossible standards when you don't even know what those standards are. Stop dancing, cut the strings and stop caring so much about whether or not he's happy, because he certainly doesn't care whether you are.
The answers to the big questions will come as your confidence increases and you become more sure that you are not to blame for everything but for now you really need to start thinking of yourself again. He has trained you to centre him with his moods and controlling behaviour but that only works while you can't see it, now you can so it's time to stop dancing to his tune.