Hello!
I'm hoping to get a perspective on this from both a male and females POV, particularly as I'd be interested to see how other guys feel about this situation and if I might actually be unreasonable/asking too much.

I've been with my bf almost 10 years now and it's pretty much been a wonderful relationship, and still is. His biggest gift to me is his constant support and love, even when I might be being a bit difficult and he's always so positive about us and our future. I've been doing my PhD over the past few years and it has no doubt been the hardest time of my life, ever. I've been mentally destroyed and totally isolated and he's been there every step to support me and I'm finally coming to the end of it and looking forward to having my life back again.

We do have a wonderful relationship, but we all have flaws and his biggest one which bothers me at certain times is his dislike for generally making an effort with family. We live only an hour or so from his family because I got my PhD place at a university closer to his home because I knew he would like to be by the coast which means I am a good 4 hours or so (and an expensive trip!) from all of my family and friends. It's generally fine and my parents are split so I have a tough relationship anyway with my Mum but we are getting older and talking about kids in the future and I had hoped he would make a bit more of an effort with my family, given I live so far from them.

I haven't gone back to see them much because of my PhD and the unbelievable stress and anxiety I'm facing but when I do it's always on my own. He never wants to join me because he doesn't enjoy hanging out with them, he'd rather stay home. For special occasions I have forced him to come, but we have literally had about 2 special occasions in the 10 years we've been together. Also, when my Mum or Dad come to visit here he is so reluctant to do anything with them at all. He really likes cycling (as do I) so my Dad brings his bike down so the three of us can go out and it was a full blown argument with my bf to get him to join us because the "ride would be too boring for him". It's hurtful for him to dislike hanging out so much with my family. My Mum is a bit nuts and I fully understand sometimes she can be a lot but honestly, he sees my parents maybe once a year and that's only when they come down. My Dad is a really lovely man, and he knows I love him to bits but he has nothing in common with him (apparently...) so cba to make an effort. He's always very supportive of me going off and doing stuff on my own with my family but every time I want him to join, there's a conflict. Equally, my parents get upset when he doesn't join and they always ask "where's your bf, how come he didnt want to join" and I hate making excuses for him.

On the flip side, I'm fed up of seeing his family but he also doesn't care about not seeing them. But there have been like birthdays for his Dad/Mum etc. which I've gone down for but he would never join for my parents. I see his family easily 5-6 times a year and I go because I know it will make them happy even though I genuinely have the most boring time. He tells me I don't have to go and I know he means it, but I know if I don't go his family would be disappointed. I guess it's a difference between me caring about what other people think and him just not.

I don't know how to handle this situation anymore and really not sure what is right or wrong (there probably isn't a right or wrong)! Am I being unreasonable to ask him to just try a bit harder? I would like him to come up to where I used to live maybe once a year at least for a weekend and actually make an effort to see my family but he just doesn't understand why he has to.

I'm hoping to be engaged soon once my PhD is done and he's had a million hints and said it will happen, but he has to know that my family will want to spend a bit more time with him than currently is the case and I don't think that is an unreasonable request. My younger sister recently got engaged and they went up to see my cousins and their new babies for a weekend and zero complaint from her partner about it. I mentioned it to my bf and he just said "yea idk why he would want to go, coz i wouldnt".

Anyway, you get the picture. Any advice would be massively appreciated because I need to finish this bloody thesis but this niggle is taking over my mind and anxiety!

Thank you in advance, guys!

Yep, difficult situation. But you shouldn't push him. Relation with relatives is always a problem. You need to act gently and little by little. Don't try to make long hard conversations with him about it.
The situation when people live together without official marriage creates some misunderstanding: for a woman, it is already family but for a man, it is just live together and nothing more, he is free to end it at any time. For this reason, he is not comfortable to meet with your parents because it would like more serious and he has obligations with more people.