I am a medicine student (F27) with only a student loan for income and my long distance boyfriend (M27) has had a well paying job with no rent for more than 5 years, is it wrong that I would like him to pay for more expenses on holidays/flights to visit him etc.?

Me and my boyfriend have been together for 8 years. We met at university when I was doing my first degree and trying to get into medicine. I got into medicine 5 years ago and have been living off my student loan ever since. My medicine degree is also in another country and he agreed that we would continue long distance and just see how it all goes, so far so good.
We try and visit each other every other weekend, mostly I have to fly to him because flights to me are very expensive and as a student I have a few more days off and can book better flight times.
He earns around 4x what I do with my student loan but with flights over to visit he wants to split everything 50/50 as in I pay my flights and he pays his.
We recently went on a road trip holiday and he booked all of the hotels. What I found out on the trip was he had booked hotels of over a 100E a night. The total cost of the trip was over 2000 E and I had paid around 600E by paying for food and bits and pieces. When we worked out the cost of the trip he split everything except 2 expensive dinners between the two of us which worked out to me having to pay 1100 E. He said to reduce the burden of the 500E I could set up a standing order of 40E a month to pay him back.
I don't know anyone in the same situation I am in being a student with a working boyfriend and don't know how to manage my expectations. Things were manageable for the past 5 years but now I am planning to move to him once I am done with my degree its feeling more complicated than before as I am now planning to move my life for him in a year.
**TL;DR;** : Bf earns four times what my student loan is. How much should I pay of our holidays/ flights to see each other (long distance)?


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