Someone has asked the speaker to act as if the two of them never met, as if the whole relationship can be wiped away. The speaker refuses, flatly: "that's impossible." You can't unknow a person or undo the time you spent together.
Then comes the twist in the last two lines. The speaker says it would actually be easier to pretend they still love each other. That small admission carries a lot. It suggests the feeling hasn't fully gone, or that the speaker finds it simpler to keep up the old story than to erase it. Either way, the love is still there in some form, even if it's painful or unwanted.
The mood is quiet, tired, and a little bitter. The short lines and plain wording make it sound like someone speaking calmly while hurting underneath. The title, "Still," works two ways: love that continues, and a stillness, a stuck feeling, after things have ended.