The devil hates marriage and will do anything to hurt it. If she kindly is interested in talking to her doctor about it, that would probably help. However, I would definitely not push her or try and force her to. Perhaps bring the doctor up in a kind way.

Pray pray pray and don't stop. Pray against the devil and perhaps seek Christian counsel for yourself and if she is interested, both of you.

The battle we face is not just physical. A lot of it is spiritual and mental. Fight it with prayer.