I'm sorry that you are so upset, but I'm glad you found our forum so you can get some answers that will hopefully help calm you down. Just please keep in mind that severe emotional stress can be a medical emergency, and call locally for help if you need it, such as your doctor or even any emergency line.
The problem might be that in a distressed state, it is very hard to do significant, clear-eyed internet research. When we are upset, we are naturally inclined to absorb only the worst possible information, or even total disinformation.
As it happens, SCL-70 is positive in around 25% of lupus patients. Lupus and scleroderma can both be rather mild or very serious, so I'm not sure why you would particularly prefer lupus, or why it would be more comforting to you, but perhaps that is because lupus is a more familiar term than scleroderma and you may be familiar with famous people who are living successfully with it.
The general rule of thumb they have is that if we feel emotionally disturbed for two weeks after a major stressor (or severely distressed over anything), we should see our doctor to see what can be done. Sometimes all we need is a bit of reassurance, other times we may need medication and/or counseling to help us make a healthy adjustment with whatever challenge we are facing.
Please keep in touch and let us know how you are doing. And of course, be aware that none of us are psychologists or medical professionals, so we can't take you by the hand and steer you to the safe zone. That is why having local professionals (doctors, counselors) to help is downright necessary for most of us when first confronted with serious illness issues.
I'm sending lots of warm hugs your way!