I've been thinking about two things: exercise and cussing.
I'm increasingly convinced that the reason I made it as far as I did through chemotherapy with any useful energy (such as it may be) is that I've exercised every damned day. I think I've missed perhaps two (non-pump) days in the last six months, plus when I'm on the pump it's different anyway. Every morning I spend at least thirty minutes getting my heart rate up and making my body move. I do it when I first wake up, because whatever energy I do have for the day is at its maxima then. Early in chemo I'd collapse around 4 or 5. These days, if I make it til noon in full-on mode, I'm lucky. But without the exercise, I might have wound up bed-ridden or nearly so. A thing that drives my heart.
Another thing that drives my heart is my commitment to kindness. For example, in social matters, one way I evaluate a person (friend, date, whatever) is whether they're nice to waitpeople. The "be kind to waiters" test tells you a lot about a person. Yesterday, my memory jogged as it occurred to me where I had first turned the inner corner on that. It was when I stopped cussing at other people while I drive. (Well, okay, it still happens on occasion, but far more rarely.) When I was younger, I'd scream my frustrations in the form of obscenities and nasty remarks at the people going too slow/too fast/where I wanted to in my way/cutting me off in the crosswalk/etc. I said a lot of things to rear windshields I'd never have dreamed, even then, of saying to people's faces. Anonymity is mightily empowering to rage, and not much is more anonymous than an automobile in traffic. What I finally realized was that I was programming myself to respond to incidents with anger instead of thoughtfulness, to drive (and behave) more dangerously, and ultimately, some really crappy behavior modeling for my daughter when she came along. None of that was worth the momentary warm glow of righteous indignation brought on by telling off some idiot who really deserved it. (Not to mention how wrong I probably was about other people most of the time.)
These days when someone blows by me in the crosswalk, breaking the law and endangering my life for the sake of a fraction of a minute's more progress down the road, I step out behind them with a big cheery smile and wave and shout "Thank you!" It's fairly passive aggressive of me, but it beats the hell out of just being aggressive, amuses me, and often amuses other drivers and pedestrians. More to the point, if they actually notice me, I'm not retroactively justifying their misdeeds by flipping them off or something. Maybe they'll even think about what just happened in some mode other than dismissive, defensive anger. I'm not quite so demonstrative behind the wheel, as frustration still leaks in and such broad communication is rarely possible (unless I have the top down), but I also try not to say or do anything I wouldn't say or do to the other driver face to face, in public.
Exercise is good for my heart. Kindness is good for my heart. Both help me focus on what's really important, including the battles that actually need fighting.