lyophobe
/ˌlaɪoʊˈfoʊbi/ or /ˈlaɪoʊfəbi/Definitions
1. noun
A person who fears being alone or deserted by others
“She had become a lyophobe after experiencing a lonely childhood.”
2. noun
One who is afraid of solitude or the thought of being left to oneself
“His lyophobe tendencies led him to constantly seek companionship.”