I remember Epicureanism being described as altruistic hedonism
Yes, but that's another example of why categories are dangerous. What is "atruism"? Putting others first always? That would certainly not be Epicurean. What is "hedonism?" Putting pleasure first always? Yes, from a certain perspective, but absolutely no from a moment to moment perspective, because we often choose pain to avoid worse pain or pursue greater pleasure. And here is where I particularly agree with Elli's criticism of "ism's" - anything that suggests a single goal that orients every other decision (other than pleasure) is going to be a bad idea at certain times. And even "pleasure-ism" doesn't accurately convey the point to most people. If you insisted on an "ism" -- the only one that would be most consistent with Epicurus' full worldview would be "Epicureanism" -- which does not appear to be the way even the ancient Epicurean's phrased it.
Just today, I found myself thinking that the thing which prevents me from inflicting pain on someone is altruism and the wish to make their lives better- that's my definition of love.
That may be your definition of love, but then "love" isn't the ultimate value in the Epicurean worldview, so has to be treated with caution too.
As you observed smoothkiwi in another recent thread, not every example of prudent eating is Epicurean. Not every instance of "common sense" is Epicurean, and by similar token not every instance of love, or even of pleasure, is something that Epicurus advised everyone to engage in all the time.
I don't intend this to sound harsh of course but it's really challenging to think through the implications of what Epicurus is teaching. It doesn't add up to "god is love" or even "the universe is pleasure" or any kind of master intention-based plan of action that applies everywhere and all the time. "Pleasure" probably comes the closest to the universal motivating force, but every time we say that we need to remember that Epicurus was plain that we don't choose every immediate pleasure.