That time of the year again

In the past, gardening has been my outlet. This year I wonder if it isn't just becoming depressing. Sunday I planted all my annuals and did a little puttsing and pruning. I was standing on the porch admiring my half completed work when some @$$hole rode his bike over a flower. I heard it snap. I yelled and he didn't even look at me. He just kept going.

Last year I lost my gardening angel - guardian angel? It was in my bird bath overlooking the garden. With the emergence of spring, I found that I am missing some of my iron fence sections and the corner brick from my corner garden. This brick had to be cut special to fit in that corner spot. It had angular cuts more than any other brick and will be difficult to replace.
One, possibly two of my rhododendrons didn't make the last bit of sun last year after the tree was cut down. Last night, two girls came by and picked flowers that I hadn't yet noticed emerging. Damn.

What to do? What can I safely and legally do to reduce enticement and deter these creeps? I have thought of wiring them to release an electric charge when touched. I have thought of adding volumes of vaseline to the points one could pick things up, but then thought of the mess and possibility of bugs and stuff sticking to them.

What makes me the most miserable is knowing how this formerly relaxing hobby that drew admiring walkers from all over the neighborhood is stressing me out. What can I put out this year? What is disposable that I can put out and not be upset about? What about a sign that they are being surveilled? Help me. I am accepting suggestions and looking for that garden or yard that has all my ornamentation.