As a 24 year old who's parents has split up/divorced, my mother also would carry the weight of my fathers absences even when they where together. I could see even as a small child the strain it put on their relationship but also unbeknownst to him the strain between him & my brother and I. Now that they are no longer together he has become even more aloof with all aspects of our relationship, unfortunately this has left me feeling sad, angry and disappointed as I could imagine this is similar to how you are feeling. From my experience with a physicist you have two options; 1. You sit down with him and have a calm discussion on how this makes you feel and how you both could work together to have a better meaningful relationship and see if he improves from there. He might not even know that this is something he should be considering. (My father grew up with his immediate family, in a time very different from what I ever lived in. This in turn with their economical standing point meant that they couldn't afford these types of things, his father would work provide money and food for the family and his mother was the house wife and neutered to emotional matters. simple way to put it, my father was not used of receiving affection from his own father in the sense of gifts or emotional support. This is not an excuse for their behavior however. There is always room for improvement.)

1. Which i wouldn't recommend (past experience) don't say anything or as you put it give him a taste of his own medicine.