Loosing at both ends is not your fault, and you shouldn't have blamed yourself for not attending the job interview. you did exactly what every other people will do, When two opportunities come in at the same time, we try to weigh the two and go for the one with more benefits. Moreso if you had attended the interview, the end result may still be the same thing. Nevertheless you should have explained your serried schedule that day to your uncle. Wish you the best.