I think you misunderstood that part. He doesn't want to see him again because he's scared there will be a point where he won't be able to truly be happy for Mibu. He doesn't want to not be able to sincerely congratulate him on his achievements etc which is why he wants to distance himself. He thinks like that because he likes him too much to not be able to promise him sincerity for their relationship.
Also, from the way the story was going, he's not working as a photographer not because he only wants to keep it as a hobby, but rather because his inferiority complex made him think he's not good enough for it. Especially if someone like Mibu, who gets praises and awards a lot is next to him.










With each chapter, Asiel's shoulders get wider
Best comment I've seen abt this read so far