Ryuusei

Someone-with comparing painful, lacking things counted-when, tears fell

数えたら uses 〜たら, the sequential conditional 'when X happens.' Different from 〜と (always-when), 〜ば (general-if), 〜なら (topic-if): 〜たら describes a specific point-in-time event. 'When the counting was done, the tears fell.'

Sadness (subj) draws-close, back (obj) wraps-around, coldness-by heart (subj) about-to-freeze

寄り添う ('draw close to / nestle next to') is the verb for two people leaning on each other — applied here to sadness as a companion. 包み込む = 包む + 込む ('wrap-into') — the 〜込む adds the 'completely envelops' nuance.

From-when, properly become-unable-to-smile?

笑えなくなった layers three things: 笑う ('smile') → 笑える (potential 'be able to smile') → 笑えない (negative 'cannot smile') → 笑えなくなる ('come to not be able to smile') → past tense. The chain compresses 'reached the state of being unable to.'

Past-to return reset-button as-for, doesn't-exist because

リセットボタン ('reset button') is the gaming-vocabulary metaphor — fitting for a Sword Art Online tie-in. The verb-clause 過去に戻る ('return to the past') modifies the noun ボタン directly: 'a button that returns to the past.'

Someone-in be-reflected thing only-only, can't-believe

〜だけしか〜ない is the double-restriction structure: だけ ('only') + しか ('nothing but') + ない (negative). Stronger than 〜だけ alone — the speaker is saying 'I had nothing BUT that.' Common in self-deprecating reflection.

Such me-in, go-on-living strength-such, doesn't-exist, was-thinking

〜なんてない is the dismissive negation: 'there's no such thing as ~.' なんて adds the contemptuous 'something like ~.' 強さなんてない = 'strength?' (scoff) 'doesn't exist.' The と思ってた past-progressive of thinking signals 'I held this view (and have since changed it).'

Loneliness as-for painfully, kindness as-for bittersweetly, even-so this place (subj) dear

Two parallel sentences with stems-as-conjunctions: 苦しく + 切なく chain in adverbial form before connecting to the contrastive それでも. The structure stacks two losses, then names what remains.

Yes someone-of-fault-into-doing, ran-away-it-is, realized day-from

〜のせいにする ('make it the fault of ~') = blame X. The pattern uses せい ('cause / fault') as the noun being assigned: A のせい = 'A's fault.' 〜にする ('make into') turns the assigning into a causative action. Common in self-reflection: 自分のせいにする ('blame oneself').

Always what (obj) have-been-seeing?

見てきた = 見る + 〜てくる ('have been seeing — up to now'). The 〜てくる ending compresses past + perfect aspect: the seeing started in the past and continues to the present moment. The question marks the inflection point of self-examination.

Even-if small world, even-supposing-be

たとえ ~ だとしても is the doubled-emphasis 'even if' structure: たとえ at the start telegraphs concession, だとしても at the end completes it. Both halves can stand alone, but together they signal 'this concession is unusually strong.'

Someday a star (subj) night-sky race-through, all-of-darkness (obj) illuminate day-until

駆け抜ける ('race-through') is 駆ける ('gallop / race') + 抜ける ('pass through / get through'). The 〜抜ける suffix gives 'all the way through.' The image: a shooting star (流星) streaking the entire night sky.

Going-it-is, however-much wished-even-if

願ったって is the casual contraction of 願っても ('even if I wish'). The 〜たって ending we've seen in Independence and other songs. どんなに...たって ('no matter how much ~') is one of the strongest concession structures in Japanese.