take a licking but keep on ticking
To continue to function, endure, or persevere despite suffering injuries, damage, setbacks, losses, failures, etc. Taken from an advertisement for Timex wrist-watches: "It takes a Licking and keeps on ticking." When you're younger, your body can take a licking but keep on ticking, so it's easy to fall into a false sense of invulnerability. This old truck of mine has taken quite a licking over the years, but it just keeps on ticking.