In both situations, the gossiper and the friend, you are wishing you know what they are thinking.

So much energy goes into that wish and it is futile energy because we can't know what another person is thinking. Be yourself, let go of wanting to know what they think (and the idea that by knowing what they think, you can control the gossiping or the friendship). Relax and be you. If the gossiper chooses to gossip, she will and you can decide then how to handle that; but for now there is no gossip to deal with and you can't prevent / control it. The friendship will remain if both parties want it to, and that's how all friendships are. If you think you want to talk more about it directly, then ask your friend out for coffee and talk more about it.

Practice reminding yourself that you can't know the unknown, you can't know what others are thinking because we are all separate persons. It is releiving when we realize we don't have to spend energy on things that don't require our energy.