repressed
Denial or abnegation of emotions and desires. The repressed emotion may resurface periodically or explosively. Though this frequently refers to sexual repression, one can also repress other emotions such as anger or sadness. This behavior is often practiced by adherents of religion and other philosophies with strict rules.
Note that this is distinct from situations like orgasm denial and no nut November; a repressed character genuinely believes their desires are negative and represses them for moral or psychological reasons, rather than as a form of delayed gratification.
Frequently involves self-loathing. A character who struggles to maintain their repression may be conflicted.