Marlene sits next to 4 phonetic neighbors — Arlene, Charline, and Darlene are the closest matches by sound. Most share Marlene's German-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"wished-for child"
"my light"
"holy, blessed (folk connection)"
"from the Tinsley place (South Yorkshire)"
"royal child of heaven"
"noble one by the lake"
"heavens and flowing water"
"calla lily flower"
"feminine form of Charles"
"everything is all right; peaceful harmony"
"meadow near the hill"
"shining, glowing"
"illustrious, brilliant"
"the one who holds up the heavens"
"graceful beauty"
"royal dignity, sovereign power"
"princess, noblewoman"
"Jay + lake (modern coinage)"
"rose lake, rose by the water"
"wide island"
"dark-complexioned"
Similar sound: These names share phonetic patterns with Marlene — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew (via Maria) origins, giving them the same cultural heritage as Marlene.
Rhythm: Marlene is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.