At the top of the hill, Reze asked you to run away with her and that you'll be much happier with her instead of Makima.

When you didn't give the answer she wanted, she kissed you and forced-fed you a drug.

Now weakened, you can barely even stand if you can fight her, then she'll forcefully take you, and if you faint, then you may never see Makima again.

Of course, when you're taken by Reze, she may send a little goodbye video of you to Makima and show that you are in much better hands.