I am on a team of juniors whose purpose is to support other, more senior, teams by handling common logistical things that the senior teams don't have time or expertise for. For example, we handle booking space, setting up meetings, we are in charge of common equipment that teams can use etc.
One senior team lead, let's call her Alice, always enjoyed spending time with the junior team. In the past it has been excessive, and Alice has a tendency of turning a work conversation into an hour-long discussion about what her team is doing. She also meets with the junior team excessively - upwards of two hour meetings - to explain the reasoning that her team needs various services from us. Most other team leads just do this in an email and get what they need.
In general, Alice has asked for a disproportionate amount of time and resources from us, which hasn't been a major problem in the past but is becoming so now because of company growth. Some of Alice's prior requests have been basically to do work that some of her team members should do but don't have time for, and are requests that go well beyond the scope of our mandate on the junior team.
My supervisor sat us all down, including Alice, to explain that we would have to divert some of the support that we've been giving her since she's asking for things beyond our scope and we need to help the other teams as well.
Alice got very angry, and told us that she felt betrayed. She felt that she was giving us all mentorship advice by explaining how her team worked, and also that she was giving us career growth opportunities by having us do some of her team's work. It is true that often members of the junior team move into one of the senior teams, to be fair.
The problems are that none of us knew we were being mentored, none of us asked to be mentored, and none of us really needed it. However, Alice has always been nice to us and we appreciate that. We also will need to work with a now-hurt Alice many times in the future.
How should we proceed with this relationship in a way that clearly sets boundaries without further harming our relationship to Alice? We all sort of feel bad that she thought she was mentoring us and we had no clue, but we simply can't spend that much time on her team's stuff any more...