Just found out how well off my dads side of the family are and now I am resentful

Semi-Target Refugee

Just a preface: There's no one I can really tell this to and I have had this bottled up for too long and I'd rather lose a testicle than post on the cringetopia that is Reddit.

(I can't give examples and will be very vague so not to dox myself) 

Starting from the beginning, my parents divorced when I was an infant and I had no contact with my dad until I was 10 after which he started taking me on these amazing holidays every other year (I later found out it was because my grandma pressured him). My mum was always vague about what my dad and the rest of the family did but I had the idea they were comfortable. 

Fast-forward to last year when I got into contact with my cousin who is an international student here in the UK and was shocked at his lifestyle and as I was integrated more into the family I learnt it only got worse.

I love my family to death but I'm starting to think me and my sister were thrown out to the wolves. We were raised by a single mother whose qualifications were not recognised so the only jobs she really only could do were low paying ones. At one point we were in social housing and on benefits while my half-brothers/sisters and cousins went to the best private schools and worried about what car to buy next. 

Growing up I didn't think I was poor all thanks to my mum but looking back and knowing what I do know now, how can I not be resentful? How can you potentially have an 8 figure net worth and let your children spend a whole summer in a hostel? I know my mum is a very proud person and will never admit to someone she is struggling but as a father you should be involved in your children's lives. 

What made me so undeserving compared to his other kids? I'm the most successful academically, I don't have any major issues or come with excess baggage that makes me difficult and I have always been a good son who listens to everything he says. 

I understand this comes of extremely entitled but I just assumed you would try to provide the same quality of life to all your children. Since finding out, I can't see him the same way. I used to show off about my dad and how cool I thought he was and now I struggle to say "I love you" back during phone calls. 

The purpose of this post isn't to wallow in self-pity and show how much of a "victim" I am as I don't see myself in that way. For the most part, I had a happy childhood and don't have many complaints. I just want to know if I am being stupid and I should be grateful for what I have? I do get financial support from my dad and I would say I have it pretty easy right now especially compared to some of my friends who have to work part-time jobs on top of uni. However, every time I think about it, it upsets me. Is this even a logical response? I know he is trying so hard to be a good dad but then I see the next status up-date from one of my siblings and see the inequity in our treatment.

TLDR:

Found out my dad is rich, my half-siblings grew up in mansions while I grew up in social housing and I hate him for it. 

(Sorry for any grammatical mistakes, I'm posting this around 1 am after completing a 12hr assessment)

Cool story. Never happened.