agreed it was far too in your face i think

They already said months ago they wouldn't be killing her when they were talking about the future of her character. They also wouldn't reveal something like that in a trailer. That whole part was clearly showing Kylo is still having hesitations against the dark side. What probably will happen is that he originally doesn't know his mother is on the ship and then senses her at the last second and pulls back. Think back to ROTJ when Luke was on the shuttle going to Endor and it kept flipping back to Vader sensing Luke and Luke realizing it. This trailer was meant to be a fake out and apparently, it worked if so many are gullible to believe it.