As my colleagues have intimated, it appears that you are in (perhaps considerably) over your head here. A few points to consider:
1) On an I-130 denial, you can supplement (i.e. submit additional evidence) the record on a motion to reopen. You cannot supplement it on an appeal to the BIA. Thus, it appears that the fact that the BIA will not receive your a "supplement" does not result in any prejudice to you. The BIA can only review what was used by USCIS to make it's decision (note you said you filed a supplement to your appeal not MTR)..
2) The process of appealing the denial of an I-130 is extremely slow. It is often better to file a new I-130 and start with a clean record. You are not prevented from filing another I-130 just because an appeal is pending. Moreover, obtaining an adverse decision from the BIA can actually hurt you if you want to try this in the future.
3) The fact that this has gone on for 3+ years (not including the time the I-130 was originally pending) is excessive. Depending on the fact of your case, however, it may be useful in obtaining a remand from the BIA.
How best to proceed in your case will depend upon its specific facts. The fact that you have let this go on for 3+ years is not promising. I recommend that you consult with an experienced immigration attorney who can review your case and advise you how best to proceed.
While this answer is provided by a Florida Bar Certified Expert in Immigration and Nationality Law, it is for general information purposes only and an attorney/client relationship is neither intended nor created. You should seek out qualified counsel to review your case and provide you with advice specific to your situation. Call +1-561-478-5353 to schedule a consultation with Mr. Devore.
I know this may seem obvious but ... why do I see you saying that "I" sent this and "I" sent that?
This is not something you should do yourself.
Find an attorney ... as-soon-as-possible.
If you are low income go here: www.justice.gov/eoir/probono/states.htm or http://www.immigrationlawhelp.org/
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
I STRONGLY agree.
I doubt you cut your own hair.....most people don't. However, an argument can strongly be made that your entire future, which is dependent on your immigration filing, is way more important to you than a haircut. Also, hair studios near me do not require 7 years of post high-school education to be able to practice the profession. So, if you won't cut your own hair because you are likely to mess it up, I urge you to take your immigration issue and apply the same logic starting today. Your likely to find we're more valuable than you may have once thought, considering my example and your experience supra. (that's a cool term I picked up somewhere in my training) Your DIY immigration hat needs to be retired, immediately. Cheers, and good luck!