While reading your post, I believe, my opinion
, he doesn't want to see you give up. Maybe, it's his way, of trying to help you keep going, by "putting the relationship in the table."
First of all, while it's extremely difficult to do, you need to quit beating yourself up. I've learned, through years of experience, it doesn't help you, it hinders you. While, I've had times, in my own life, where I just couldn't find a job and beat myself up for it, it made things harder for me. When I would go to job interviews, it was almost like they could see my "desperation" to aquire that job.
My suggestion, for you. First of all, try to start adjusting yourself, to go to sleep earlier. You can take a bath, listen to calming music, light candles/incents. It's trying to help your mind any body, get ready for sleep. You'd be suprised, at how it may help you. Next, when you do have an interview, watch something funny, before you go!
The reason I say that, is you're going to be in a better mood and also, "project yourself better." I use to do that, before an interview. I would watch a movie, that I know would make me laugh! When I went in for the interview, it seemed as though, I was more relaxed and answered their interview questions a lot faster and with better responses.
For "changing yourself." I don't believe we need to change, unless we truly see the need for it. If there's something you feel you need to work on, then do what you feel's best for you. I understand, how much you care for this person, but him "holding" a relationship on you, isn't helping you, when you're already upset. Maybe, you should explain that to him. Just my thinking
. IF you do decide to, just explain, it doesn't help you, it hurts you. Maybe, he'll "adjust" the way he treats you. Maybe he thinks, this is going to "motivating you," when it truly seems to be causing you more stress. I also would sit down and explain to him, that while no one person is perfect, we all have our flaws, you truly need his support. I sincerely hope, that he'll help, be more understanding, and try to motivate you, in better ways, that are not going to make you feel the way you do now. People, sometimes, just don't understand, that what they say and how they say things, hurt us, not help us.