Yes, dear. I understand that. So, you would need to show where you got the money - that it was not his drug money being laundered. You would need to show that you LEGALLY EARNED the money and paid taxes on it - or that you inherited the money. That would be the only way that you would be able to show that it was not HIS drug money.
Short of that, I have no suggestions for you not being indicted. If he is not a drug dealer, then tell the truth. Do not take the Fifth. Have documents that can be presented showing you earned the money or that the money was some type of inheritance -
I still suggest, if you have not already done so, consult with a local attorney and NOT your BF's attorney. You need to have separate representation. Contact the Pennsylvania Bar Association for a referral.
You can say all day long that they money is not drug money, but unless you can show a legitmate resource for the money then they are going to win - because they are going to show drug deal after drug deal. If you did not know or was not aware of these matters, then a local attorney is going to be able to assist you - perhaps, get them to offer you a plea agreement of some type.
This has to be very stressful for you - consult with a local attorney will help you to relax somewhat