Some random thoughts...
'Plan B'/'consolation prize' thoughts are, IMO, lines of self-talk that are normal. Human beings are self-centered, and believing that we caused our partner to cheat gives the BS a weird sense of power over the sitch.
The antidote is to change your self-talk. Bluerthanblue's realization that she's the prize is one aspect of changed self-talk. It's also a change that brings BSes closer to reality. The WS may look great, make a big income, etc., etc., etc., but WSes cheated, and they haven't healed themselves yet.
The sooner you change your self-talk, the sooner you'll heal. Your WS can help by being honest consistently from now on and by showing how much she desires you in big and, more important I think, lots of little ways. Even with less than total change in your self-talk, consistent loving behavior by your W for a few years is a big help in not feeling like plan B.
But the real cure is knowing in your gut that you're the prize, even though you're as imperfect as the rest of us.
A good IC can help.
*****
It's probably better not to commit to one solution or another until you're well out of shock and into your healing, but you did. My reco is the same as it would be if you hadn't committed, though, so you may not have lost much of anything by committing to R more quickly than ideal.
Now is a time to test your W. Ask questions, and evaluate her answers. Honest answers are positive for R; dishonest answers are positive for D.
Figure out what your requirements are for R, and ask your W to sign on. Delivering what she agrees to is positive for R; not delivering is positive for D.
Raise issues as early as you can and find out if your W will work with you to resolve them.
Share you feelings with her. If you're angry, tell her you're annoyed/angry/furious - and use a tone of voice and body language that show you're angry. If R is going well, experiment with showing her your fear, grief, and shame. If she can't handle your feelings or if she uses her feelings against you, R probably isn't a good choice.
Bottom line: be yourself. Encourage her to be herself. If you're not a good fit for each other, or if one of you isn't all-in for R, the earlier you find out, the better.
One way of describing healing is 'getting authentic'. Be yourselves. You were teens when you met, right? SO you've grown up together. There must be things you like about each other. Are they enough to make you want to spend the rest of your lives together? If so, R is possible. If not, you can split honorably with your head held high.
*****
I didn't fear another A, but I did fear that my W was biding her time until she decided to leave.
I think these sorts of fears are unavoidable aspects of R. We can't predict the future, and BSes know they've been fooled by their WSes already, so they can be fooled again.
And again, the main way for this fear to dissipate is consistent behavior over time. You have to be patient.
There's another side to that, though. Just as you need to realize you're the prize, you need to realize you can recover if your W betrays you again.
IOW, have some faith in yourself.
[This message edited by SI Staff at 9:59 PM, Monday, March 11th]