worried about my boyfriend

my boyfriend and I have been together for about 9months now. i'm in year 13 and he would be too, but he dropped out to study at home (towards the end of year 12) because he struggles with anxiety and depression. my a levels are this year and his btecs would be too, but hes decided that he's ****ed it up by not doing any work and isn't going to do the exams til next year.
i feel like he puts a lot of blame on his mental health and doesn't take responsibility for his actions; i understand it affecting him because i suffer from depression too, but i feel like he lets it take over and define him as he also blames all of our arguments on his anxiety and him not being able to do anything on his depression. he did therapy (he hasnt yet applied for the adult one as hes 18 now) and says he really wants to "get rid" of his mental illnesses but he doesnt actively make an effort to. maybe i dont understand it because i dont suffer from depression as badly as he does? or am i just making excuses for him? i dont know how to bring it up without sounding insensitive because its quite an accusation.

perhaps im being pessimistic about it since his exams only postponed by a year, but im worried itll just keep being postponed and nothing will happen, and i don't particularly want to be carrying someone on my back throughout uni and my life, and i know my parents won't approve (especially as asian parents)
i want to talk to him about it but whenever i do he immediately shuts it down and its like ive ruined the atmosphere and i feel bad :/
idont know what to do