Bit of a tricky subject, this: there's a quote (which, needless to say, I can't exactly remember) which says something along the lines of "you can't chose your family but, thank God, you can chose your friends". There's a terrible pressure to be a loving son/daughter/whatever but it's not always fair to expect people to do so.
I adored my mother but have always had a prickly relationship with my father, who basically b*g99ered off abroad with a younger woman when we were kids, and left my mum without financial or any other kind of support. Inevitably, my mother died relatively young, in her fifties, whilst my dad is still with us, at nearly 90, and back in the UK. He is a grumpy, disagreeable and racist old man, who suddenly started wanting to play happy families 20 years ago, when we had kids, and who apparently complains to others that we hardly ever let him see his grandchildren (who don't exactly find him a barrel of laughs). The irony of the fact that he hardly saw his own kids for years, apparently escapes him. The only saving grace is that he is still with the "younger woman", who is only in her early 70s and, as such, is able to drive him around, and generally look after him, thus saving myself, my wife and my brother and his girlfriend from having to do so.
Arguably I'm not a very good son, but I know exactly how you feel and I have a checklist of behaviours to avoid in the interest of (I hope) maintaining a better relationship with my kids than I have done with my dad

. I'm lucky, in that my In-laws are great, and I have always got on very well with them, so I feel as if they are substitute parents, in many ways.
Looks like I needed a good rant as well and I'm, erm, a fair bit older than you! Don't beat yourself up about your relationship with your parents: families are sent to try us

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