Should I initiate R talk?

[MrBond]

"So now I'm out of a plan."

No your plan is to not engage your W.

"I need to do something."

You are. You're giving her the space she asked for. Start looking up C for your D.

"I told her calmly, not to worry if there was someone else, that we were no longer together and that it wasn't like cheating. "

BS. It is cheating plain and simple. Don't EVER belittle this fact. It will come back to bite you in the butt. You don't want an OM in the picture to confuse your W more.

"but now, i'm wondering if she got angry because she thought I was the one with OP in the picture."

You're mindreading. You can't predict what your W is feeling or thinking so don't even try. Just do what you can for you and your D.

"Should i dispel her fears if any?

No.

Or should I just stay mysterious and kind?"

No. Just be yourself and don't include her in your plans. Imagine her like a neighbor or casual acquaintance.