Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:2/2
K:Bmin
['E2 FE DB, B,2 DB, A,2 B,E', 'FBAF A2 FA Bdeg fdde f2 af', 'F3 D', 'DB,A,D B,E E2 FEDE', '(3Bcd eg fede']  
X:1
L:1/8
M:2/2
K:Bmin
 F2 AF E2 FE | DB, B,2 DB, A,2 | B,E E2 FEDE | FB B2 dBBA | F3 D E2 FE | DB, B,2 DB, A,2 | 
 B,E E2 FEDE | FBBA B3 A :: FBAF A2 FA | Bdeg fdde | f2 af egfe | dfed BAFE | FBAF A2 FA | 
 Bdeg fdde | f2 af egfe | dBAF B3 A :|"^Variations:" |: F3 D E2 FE | DB,EB, DB,A,D | B,E E2 FEDE | 
 FABc dcBA | FBAF EGFE | DB, B,2 DB,A,D | B,E E2 FEDE | FBBA B3 A :: F2 BF ABdA | (3Bcd eg fede | 
 f2 af gefe | dBAd BAFE | FBAF A2 FA | (3Bcd eg fede | fgaf (3efg fe | dBAF B3 A :|  