Right now, you still feel married, which means that you still are where it matters most: in your heart. The wedding ring and the relationship status are both visible symbols of your vows to Jane and yourself, whether she is with you in body or only in spirit.

If it is too difficult, then maybe it is not the time. You have spoken of eventually moving on, and that is a decision you may come to. I have known those in your position who maintained the symbols of their marriage for the rest of their lives, and I have known those who reverently and respectfully put those things away when they found the right time for it.

I won't tell you that there is no "right" answer to this question, because there is. The thing is: only you can know that answer. It sounds like you just don't know it yet.