My guess on the series finale is this:
1. Lynette and Tom realize their marriage is over, and get a divorce, leaving her alone.
2. Susan's
a new widow, leaving her alone.
3. Gabrielle can't come to terms with Carlos' new attitude towards money, so they separate, leaving her alone.
4. Bree's cop boyfriend died and ex-husband is now gone, leaving her alone.
5. Renee's boyfriend, guilty over bringing the mob into their life, takes the fall for the body buried on his property and goes to jail, leaving her alone.
So in the end, the girls are all alone... but have each other.
If this turns out to be true, then it will be the most contrived series finale of all time.