The problem is that people expect you to be happy being alone and if you tell them you're not, they'll treat you with cliche's such as,
"it's great being alone" (even though they're not),
"you need to learn to be alone because it's good for you" (even though they've never actually done it),
"you need to man up" (even if your a woman),
"just do nothing and the perfect person will magically appear",
or the worst one... "yes i'm alone too" said while they're talking to you and just before they go home to their partner or their kids etc. So from my perspective, I'm sorry that you are alone, it sucks and yes it makes you feel depressed and tired so sleeping more is a natural reaction.
Come on here and share your feelings anytime with us if you want.