Consult with an attorney, now, not later.
Arizona is a non-recourse state, meaning if a mortgage loan was 'purchase money' to buy the home, then the lender cannot pursue you for the deficiency. HOWEVER, if your HELOC loan was NOT purchase money, then you could very well be in toruble.
Once again, this is not a legal forum, and this is not legal counsel. Reach out to a competent attorney right away.