Code:
(?<=\p{L}|\.)\s?‘(d|m|s|t|ll|re|ve)(?=\p{P}|\s)
Just look for letters, no need to look for "uppercase_letters OR lowercase_letters"
Do you anticipate any of these happening after a full stop?
Perhaps that should be fixed... I can hear there being an uppercase word, e.g. someone screaming.