Switch parties. Or at least, be an unhyphenated Independent and caucus with the Senate Republicans.
There is no reason to think that you will ever be treated with respect and dignity in the Democratic Caucus again. Even if you seek to make amends for what Senator Reid perceives to be your apostasy, you will always be viewed with suspicion and bitterness by members of the Democratic Caucus.
By contrast, Republicans will welcome you into the fold. You will help cut a Democratic majority and if your presence in the Republican Caucus helps the GOP recapture the majority in the Senate at some point down the line, you can have your chairmanship back. And if your seat makes the difference in that effort–and who knows? It might–your power will be especially and particularly enhanced.
So make the switch. Take the plunge. You have nothing to lose and everything to gain.