Four short lines carry a lot here. The speaker looks at youth, something that has moved past them, and then turns to hope, which seems to grow even though a disease is present. The word "blossoming" makes hope feel alive and unforced, like a plant that keeps opening despite bad conditions. The speaker says this hope is "the light that carries me," so it isn't just a pleasant feeling. It is what holds them up.
The last line shifts the mood. An "eternal flame" suggests something that never dies, yet it is "finally at ease," which sounds calm, even relieved. Judging by the wording, that could mean peace after struggle, or acceptance of whatever comes. The poem doesn't say which, and that openness is part of its power. The tone is quiet and gentle rather than angry or desperate. Youth may be slipping away, but the speaker finds steadiness in hope and a kind of rest at the end.