How do I gently confront my boyfriend for guilt tripping me in fights?

Hi everyone, this is the first time that I am here so I am open as book to your opinions please do share..

So for context me and boyfriend are in relationship for a 1year now we are long distance and met through a game yuppp. We had this unsaid rule " if we fight we make it right" and we usually we don't really have arguments but lately we are having arguments and if I am at the fault I accept and apologise. when he is at fault he starts this weird thing where he start talking bad himself and lowering his self esteem, as he does that I feel guilty because I know he is not in his best state rn and end up convincing and apologising to him I am mostly ok with that because it just petty arguments. sometimes I am really hurt and I want him to acknowledge that still the guilt tripping doesn't stop sometimes I do sob by myself. If you are wondering why did not I confront him I FREAKING DID but he took it wrong way and started talking shit about himself became depressive thinking he doesn't understand his girlfriend so again convinced him, so how do I confront him about this in nicest possible way I don't want to hurt him.[ sorry if you don't understand English is not my first language]

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1 mo
Thank you everyone for your advices. it were really helpful. So where do I start... yupp I have confronted him this time and he understood too. I am so happy it was tough talk but yeah and turns out it's not manipulation he indeed is depressive as he started to share things he haven't, I do really get where he is coming from. He promised if I ever feel that way again I am free to leave but also promised he will change for us& our future together & thank you lovely people for the kind advices
How do I gently confront my boyfriend for guilt tripping me in fights?
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