Equitable means fair, just, and reasonable, based on the factors set out in the law. Yes, Tennessee is an equitable distribution state. No, if the parties agree to the divorce and settle the case without a trial, which is called an irreconcilable differences divorce. Fault is only a factor for deciding alimony. As a practical reality, however, if a judge is presented with evidence of fault with respect to a request for alimony or attorney's fees, there is a common belief that the evidence ultimately could be persuasive.
Every state has different laws.
Inheritance is separate property. There are things you can do to prevent inheritance from becoming marital property subject to equitable division. Do not commingle the money by putting it in a joint bank account. Do not spend the money on your house if your house is owned jointly. It is important to note, however, that the amount of separate property is a factor in dividing marital property.