RESERVED

adj. reticent, restrained, unresponsive, controlled, silent, taciturn, uncommunicative, unforthcoming, close-mouthed, unresponsive, undemonstrative, unemotional, poker-faced, cool, formal, aloof, guarded, standoffish, unsocial, antisocial, distant, remote, detached, retiring, withdrawn, sedate, demure, dignified, guarded, prim, rigid, strait-laced, icy, frigid, ice-cold She was always very reserved, not showing any emotion