How to stop being a burden

i haven't been diagnosed yet because there are no services for personality disorders where i live but my boyfriend (who i depend on) is pretty much an expert in psychology and is 100% sure i have it. and so am i. i've never understood myself until i read that criteria. but anyway, i have upset him again today because i upset him every day by being a burden and it makes me want to kill myself. i just wish there was a way to be able to lift this burden and be able to do things on my own or without guidance because my boyfriend is much more ill than me and needs someone to care for him... but i just can't do it because i am completely incapable of everything. even in emergency situations, there are so many times he needs me to take control and just help him and i can't without strict instructions ... and even with instructions i still mess it up.

this thing, this potential disorder, has completely ruled my life since at least 11yrs old and i just am so sick of being useless and worthless. what is the point of my existence if i'm just making people unhappy wherever i go because i demand so much from them? i find it ironic that some people refer to the disorder as selfless because it makes me so selfish. i guess i just wanted to come here to rant but i also have a question for sufferers...

do you feel as though you fully move on from people you've depended on in the past? for example, an ex that you were completely dependent on, you break up and attach to someone else.. do you then completely forget and move on from the ex or do you feel like they will always be a strong part of
you? does your new partner completely take their place or do you still feel somewhat attached to everyone you've ever attached to? hope that makes sense.