I love the advice here about switching things up. Another idea is to include other people. I had one friend who always complained a lot around me; when we met with someone else, the dialogue improved a lot.  Also perhaps there's no need to get together quite so often which might also freshen things up. A chat along the lines of - I'm finding it really hard to make time for friends just now, and I want you to meet this new friend Ann who I think you'd like too. What about the three of us have lunch, a hike, an activity sometime next month when my schedule is less hectic?