I have a terrible addiction and want to kill myself

Some recommendations:
-talk to your father
-talk to local shaykh
-do hijama, ruqya
-talk to general family practice physician ASAP, ask for help
-go to psychiatrist for anti addiction treatment
-pledge for fasting as you can every second day (not must but continuing hard)
-enroll a gym and/or fitness
-enroll local community altruism projects
-enroll local masjid cleaning or education
-visit library and read at least 2-3 books weekly
-drink 100% pomegranate juice 2x200 mL daily
-take Saffron supplement
-take Nigella sativa daily
-last and maybe most important, not forget morning, evenings duas, dhikr, salawat, duas before bed
-after bath/ghusl use a thin layer of olive oil with a little bit frankincense essential oil to smear all ocer body
-read surah al Baqara every night or at least 1-4,255-257,284-286, Manzil as much as you can
-join local dhikr gatherings
-visit a shaykh for ruqyah/healing (very probably you have a lot of all sorts of evil added to you ant it is not only ypur fault)
-instal a pornblocker, write password and throw away

PS excuse me for typos like enrol, install etc.

but what about sending porn to my relative. i dont know for a fact i did or didnt, but ive been racking my brain for months worrying about if i did or didnt. so confused and so humiliated. ive humiliated myself.

I think people like this already had a lack of discipline and blame it all on other addictions when they get older, today they just teach children just to be happy more than discipline and what is good for them. Here, though you are very weak -

1. Your saying that your sin is greater so you should go to Hell
2. Plenty of evil doers don't wish to repent as others won't accept them - here they look towards people rather than Allah
3. Just because Allah forgives that doesn't mean that your life is the way you want it to be-forgiveness is for the herafter.
4. As Allah is going to keep you alive forever in the next world (your sin is not so great that you can dictate and get Allah to un make you -Allah is the Creator and your sin don't snuffle out what he has done.
5. If you wish to elevate your sin than you will be joining the people who are already on the way to Hell.
6. People have an immature, sissy outlook of what they think makes someone good and the evil people think it is just that you are good, rather than making something more important than your sin. So here, like taking care of your parents- you did not elevate this, but your sin or giving to charity etc.
7. At the time of Prophet Moses peace be upon him and they were commanded to sacrifice a cow, it was chosen from a boy who was obedient to his Mother.
8. To be disciplined is to be "obedient" and value and put other people first-placing Allah first, the Prophets, other good people, your parents etc
9. As they say, devil creates work for idle hands-looks like you've already got too much time on your hands and got a sissy outlook like someone who has been a female scorned attitude (which is not islamic-as regardless of sins you need to look towards Allah), I think what you're asking is that it just gets better and in your dealings with people as you are uncomfortable-but people are only uncomfortable as they are putting themselves first and not others.
10. If you needed to save a drowning person, your not going to be uncomfortable about yourself, you need to rush and help if you can -here an extreme example yes, but need to apply it day to day. People are deluded, they have low self-esteem as they don't always put others first and then they practise how to socialise. But if you were to help with collecting rubbish -you should be able to spring into action and not dawdle and say you got low self-esteem.
11. So there is an immature outlook on when people commit sins, they wish it went all away and they can just be as if they were virgins example. Here, you simply have to be a functioning adult-maturity. It is ridiculous to go around and say I can't do this because of my addiction, and I can't say or do this becuase of my addiction.
12. People pray to Allah for more-but you are already not doing enough with what Allah has already given you!

Feeling this dejected bc of addiction is not healthy.
The problem lies in how you think of Allah to begin with.

You seem to think you have fallen so far that Allah is incapable of forgiving you? That killing yourself is the only solution now?
Thats some warped sense of knowledge you have about Islam.

Listen there were people in the past who murdered 100 people but then got forgiveness when he did what a knowledgeable person asked him to do.
And there was a prostitute who fed a dog water during famine and got Allah's forgiveness.

So whats your point? What are you even on, brother?

look at this Hadeeth for example,

Narrated Ibn Mas`ud: A man kissed a woman (unlawfully) and then went to the Prophet (ﷺ) and informed him. Allah revealed: And offer prayers perfectly At the two ends of the day And in some hours of the night (i.e. the five compulsory prayers). Verily! good deeds remove (annul) the evil deeds (small sins) (11.114). The man asked Allah's Messenger (ﷺ), "Is it for me?" He said, "It is for all my followers."

Sahih al-Bukhari 526

He kissed a woman unlawfully and then was asked to just pray the Fard prayers and as he prays consistently it would end up wiping his sin.

And here you are saying killing yourself is the only solution when your sin cant even hold a candle to these.
Seek knowledge of the Deen, there is a post here somewhere that talks about overcoming porn.
Do you keep asking Allah to cure this every time you pray Salah? If not, start doing it ASAP.