Anonymous wrote:I guarantee you that you didn’t meet all of your milestones, that the bar has been lowered for you so that you feel like you are, and senior colleague resents you.
This is a totally bizarre response. Are OP and senior colleague battling it out here on DCUM?
OP, I'd stop keeping her in the loop as much as I possibly could, for starters, and then revise your interpretation of "in the loop." It means keeping someone informed about the progress of a project, not getting their approval.
If she complains to your management I would be apologetic and then ask for a meeting with your supervisor and grill them about their expectations for keeping this colleague in the loop and for getting her approval. You have to do this with some nuance, but everyone is playing a game here - you need to understand the unspoken rules to play effectively.