Oh...Horsefeathers. (i need your help)

Im Autistic, i get upset over things that most people can easily deal with. Through my whole life, my computer shave been a lone light, Each one being loved and cared for as long as it could hold out until the day came when it was time to let it go. This one, named "Perseus" was the first one i ever bought and paid for myself, clocking in at £450. I saved for so long to have him...I was so happy the day i brought him home, finally, a brand new PC...

But now.....almost 5 years on, hes going loco in the coco. I don't wanna think about replacing him, at all. But how much longer can repairs keep him going? Plus i hate windows 8! >.< i want 7! This one has seven...

Im sorry everypony, im rambling on. Im just upset. This accursed disability gives me heartache over such things. I hate when things change. I believe in keeping computers until the day their hardware fails, not just tossing them out soon as they start acting up, like somepony in my family does.

I dunno how else to explain it. In a world that made fark-all sense, where social interaction was a pain, and nopony else seemed to share my taste in fandoms, there came the internet, and the people on it. I cant interact very well with the world, im terrified of it most the time. But a computer removes that wretched barrier. They cant tell if whoever sits at them has a problem or not, they'll react the same. The ultimate in equality, something i never felt like i seen much of in my life. Labelled a troublesome child, stubborn, rude, even a bitch at times. But i always had the computers. When the previous machine to Perseus started to fail, i cried for ages. Even when i brought Percy home, he sat there a good few days before i could bring myself to meet this newer, shiny entrant to my closed up world.

Its been through alot, had its system fixed TWICE after it nearly collapsed. The fan at the back has had to be fixed, and now the internal ones making awful noises that a friend has told me means it may need more maintenance. Also, it makes odd sounds, locks up more and more lately, AVG is fighting to get enough resources to do its scans, causing everything else to spaz out, which it never did before..even on maximum scan setting. The drive is defragged, ive used the disk cleanup.

It comes down to this: do i fork out close to £60-£70 ($100-$115 for those in the USA) for repairs...or, with the money ive got, buy a new one? I really don't wanna replace this one.

But, and part of me feels bad for admitting this...i would love to be able to have a bit more processor power on my hands. Something i could run SFM on, you know, that application that ppl make PMVs on? I wanna learn that...but this computer holds a lot of memories for me, and i don't wanna let it go just yet..

What do i do? Theres nopony to talk to in my family about this...I need your help.