of your love for him. fighting will push him further away. make sure you say the words and let him know of your support in his life and you want the best for him. being 12 is hard and he's no doubt trying to exert his own growing independence. being "sick" from school could mean a problem at school he is having difficulty with. maybe try to draw out his thoughts a little more when he claims to be sick. remember to have lots of patience, and overall a 12 year old acting like this nothing too unusual. hope it all works out for you two!
you don't need to be 