You were still married so you still have rights in the estate. So to do his kids. It doesn't sound like they will take your word for it, so I recommend you contact a probate attorney first thing Monday morning. It is a race to the courthouse to see who gets appointed as Administrator. Expect that they may not agree to your appointment and may try to make waves but it is important to be appointed. Don't worry about not having money. There appears to be enough in the estate to cover attorney fees and costs.
This forum cannot provide what you really need-your own attorney to represent you during this tough time.
You have spousal rights-so you need to be represented.
The answer given does not imply that an attorney-client relationship has been established and your best course of action is to have legal representation in this matter.
Both Mr. Davis and Mr. Pippen give you good advice. As you might have guessed, neither your husband's two grown children nor your friend can substitute for advice of an attorney. And it seems clear that you need more than mere advice -- you need representation.
Whether your husband's kds were "missing for years" is no more relevant than that you and your husband had been separated for years. The determination as to who owns what will be made in accordance with your state's laws of intestacy.
There is one very important factor as to which your posting is not entirely clear: What does the deed say? If you and your husband owned the property jointly with right of survivorship, that would resolve the issue -- in your favor.
Find a local attorney. You can use the avvo site to find any of a number of very skilled lawyers in your local area. That you "have no money" may not be entirely relevant, because you clearly have, at the least, a substantial financial interest in the property and thus you may be able to find an attorney even without any significant upfront payment.
Good luck to you.
Michael S. Haber is a New York attorney. As such, his responses to posted inquiries, such as the one above, are limited to his understanding of law in the jurisdiction in which he practices and not to any other jurisdiction. In addition, no response to any posted inquiry should be deemed to constitute legal advice, nor to constitute the existence of an attorney/client or other contractual or fiduciary relationship, inasmuch as rendering legal advice involves the ability of the attorney to ask appropriate questions of the person seeking such advice and to thus gather appropriate information. In addition, an attorney/client relationship is formed only by specific agreement. The purpose of this answer is to provide the questioner with general information, not to outline specific legal rights and remedies.