OP if you are still reading this...
Lots of posters have said some useful things, I want to give you some info you likely won't hear this way anywhere else..
Your brain is bamboozling you...
Learning theory tells us that there are punishers, and there are reinforcers.
Punishers reduce the frequency of a behaviour.
Reinforcers increase the frequency of a behaviour.
In other words, you (all of us, anyone with an amygdala and even some without), will work to AVOID something aversive to you, that aversive is a punishment/punisher.
Your partners behaviour in smothering you, in banging his hand, in getting angry... is aversive, it reduces the frequency with which YOU do things that trigger it... you try to avoid upsetting him, you try to work out ways to appease him...
Reinforcers are the things that are nice, you work to earn them, you will repeat the behaviours that got you that nice reinforcement..
So when hes nice, hes lovely, he buys you flowers, tells you you look nice.. those are reinforcers, nothing wrong with that.
Here's where the brain bamboozles you though.
Relief is HUGELY reinforcing.
If someone uses both aversives/ positive punishment.. AND positive reinforcement ... that reinforcement comes to signal that you have successfully avoided the nasty punishment.
Your brain then values that signal that you WON'T get punished, very very highly, the relief is so INCREDIBLY reinforcing...
So you get rewarded for every time you work to avoid his punishments.
The 'lovely' things he does which are in fact just the NORMAL none abusive things, not shouting at you, not hitting you/smothering you/calling you names, become extra special in your mind.
So we get this situation where he is horrid a lot of the time, but the times he is NOT vile, NOT abusive OMG he is the most wonderful man on the earth he is so lovely.....
It isn't real. Your brain has been conditioned to fear punishment and crave relieve, you are going to actively seek out those reinforcers and see them as more than what they really are.
Please get out of this relationship.