I understand why you are sad but if the outcome ends up being you and xBF together, happy, and healthy, you'll be able to look back and be very glad for your sacrifice.
I know my words won't help much, but as was mentioned, just try and stay as patient as possible in this phase and keep moving forward.
I'm a big believer in things happening for a reason, so I feel you're here to learn something and grow because if it.
Still following along and offering what I can when I can, my dear.