"He lies because he’s afraid of facing up to awkward situations."
"Sounds like he’s scared of giving you the wrong answer."
gamerwidow, people in abusive relationships, lie to protect themselves.
That could be what's happening here.
OP, your relationship is controlling and bullying. To me, it sounds as though he lies to pacify you. It's the easy way out, yes, but this situation doesn't come about, in what should be an equal relationship, without a level of abusive/controlling, behaviour from the other Partner.
He's an Adult, he shouldn't need an easy way out over small things, or things that are his business, because you don't get to dissect them.
You have got into an odd Parent/Child dynamic, possibly, but if the sexes were reversed, it wouldn't be viewed as that. He would be told to get advice to get the courage to leave.
For this to go on, day-in, day-out, shows a level of emotional abuse, as well.
When you say you want him to be more assertive, are there other aspects of his life that he isn't good enough in, as far as your concerned? Do you think you should get a say in everything, is he allowed to be his own person, have his own personality?