Is it ever?

I've twice been in this situation. The first time, a girlfriend I had a normal relationship with decided to go on a sex strike. In that case, I lived with her, so I left. She was livid, saying "it shouldn't be about sex and I have no right to her body". Well yes, and you have no right to a relationship with me either. She accused me of "sexual coercion".

The second time, a very attractive girl stayed the night with me after a date and didn't go home the next day. She slept in my bed but rejected all physicality. I thought it might develop, but on the third day I tried to kiss her and she was revolted by the thought. It was obvious she was just after free room and board. I gave her an hour to get out.

I've seen arguments to treat sex as a special case in relationships, saying if one partner wants to cease sexual activity then the other partner should just tolerate it indefinitely or its "sexual coercion". I think that's BS. Sex is part of the deal, just like the other benefits and responsibilities in a relationship (which usually are implicitly understood by the couple), such as exclusivity, commitment, emotional support, trust, etc. Sex is another component of the two-way implicit agreement, it's not a special case of a unilateral option that one party can withdrawal from and everything else must proceed normally.

But, I'd like to hear counterarguments, particularly from the radfem/FDS sides.