Astigmatism vision

I heard that eyesight doesn't deteriorate much with age, but it seems to get worse over time, and my astigmatism also seems to be getting more severe. Why does astigmatism worsen, and what causes it? It's also difficult when I buy contact lenses because my vision changes daily. When I get an eye exam and they tell me my eyesight has declined, I feel more depressed and sad. Will presbyopia make things worse? I'm curious about how it feels if your eyes are bad but you develop presbyopia.