OP, you have try and see it from your lady's perspective. She is fine with it, she has no issues at all with being examined by whoever. She sounds very calm and collected. You do not own her, she is in charge of her own body. She is in control with this, not you. If she is comfortable, then you need to respect her decision.
What is happening in terms of IVF is such a draining process (emotionally and financially), if you throw your extreme emotions into it, it's a recipe for disaster. Your feelings are completely irrational (as you have acknowledged), there is absolutely nothing sexual about the world of medicine, especially IVF. If these are your genuine feelings then you need to see a mental healthcare professional ASAP. It's is very concerning and unhealthy and who knows what it will manifest into.
A forum like this will attract support but also a lot of criticism especially for views that are so extreme.
I wish you all the best in your IVF ventures but please, get yourself some help to cope with it all.