buying meat from the grocery store is not an ecosystem

That's a food web. An ecosystem incorporates the environment organisms live in and how the organisms interact within that environment. The soil, climate and weather are all part of an ecosystem.

“I was walking along the bank of a stream when I saw a mother otter with her cubs, a very endearing sight, I'm sure you'll agree. And even as I watched, the mother otter dived into the water and came up with a plump salmon, which she subdued and dragged onto a half submerged log. As she ate it, while of course it was still alive, the body split and I remember to this day the sweet pinkness of its roes as they spilled out, much to the delight of the baby otters, who scrambled over themselves to feed on the delicacy. One of nature's wonders, gentlemen. Mother and children dining upon mother and children. And that is when I first learned about evil. It is built into the very nature of the universe. Every world spins in pain. If there is any kind of supreme being, I told myself, it is up to all of us to become his moral superior.”

-Terry Pratchett, Unseen Academicals

This...plants feel pain. Mushrooms may actually be sentient. Everyone draws their own lines, it doesn't make them better or worse.

https://www.youtube.com/watch?v=eqLsus9_YsQ

Have you tried some good alternatives to meat? Like, try seitan* crumbles in a taco. With all the spices and other toppings it's really hard to tell the difference. Also, I find it almost impossible to tell an Impossible Whopper with Cheese from a regular Whopper with Cheese, after all the glop they put on it. I know those are both bottom-of-the-barrel meat choices, but maybe branch out and try a thing or two. If you don't like it - no biggie.

I've tried casually dipping my toes into the vegetarian pool with just occasional meat substitutions. Occasionally I find something that's "No way" but more often than not, I find something that is also really tasty. It's not meat, but it's also tasty in a different way, so I don't miss meat as much. I've found vegetarian dishes I actually like. My biggest problem however is getting enough protein in my diet when I start eating mostly veggies.

[* Seitan only if you can handle gluten. Because, it's like 100% gluten! ]

Hilarious