The title of this may be a bit misleading as being "single on Valentine's Day" isn't really something to beat yourself up over or let bring you down. Don't get me wrong, having someone on Valentine's Day (significant other or not) tends to make the day a little more special (or tolerable if the day typically leaves an awful, bitter taste in your mouth).
I both love and hate Valentine's Day. I hate it because I've never had good personal experiences with it. I have maybe had two or three good ones in the 24 years I've been able to experience them. Now obviously I wasn't "dating" at ages six or seven so take away a few of those years. It's still a small percentage of the days that I've genuinely enjoyed.
There's (usually) so much planning involved in celebrating, and I just don't have the time nor patience to make 17 different reservations at 31 different restaurants to make sure I get a table for an hour to eat food in a crowded place with loud noises and obnoxious people. I say obnoxious people because I have seen over a dozen couples come into places demanding seats when they don't have a reservation and then treat the staff members as if they were the human equivalent of garbage - which is NOT cool.
I'd much rather stay at home, sit on my couch, and gorge on a tub of ice cream with cheap wine and a plethora of cheesy rom-coms. I'm not interacting with terrible human beings and I get a lot of ice cream. Who doesn't want a lot of ice cream? Even if I'm by myself this is something I enjoy doing because I'm at least giving myself a pretty solid night to just take care of myself. On a day where a lot of people feel particularly lonely I'm 100 percent OK with treating myself to ice cream and cheap wine.
Now the other side - why I LOVE this day. I love this day because while I am not usually out at night, I tend to go out during the day. I see a lot of happy people who are in love and while it'll make a lot of people turn their heads and others feel terrible about themselves, i find a lot of joy in seeing other people happy and in love. I absolutely love to love, and even if I'm not in a place to love someone it's nice knowing that there are people that are.
It's not the chocolate or the gifts or the size of the bill the makes the day special, it's spending the day loving. Whether it's loving someone close to you or just you loving yourself, make sure you find space to love. It's corny but the world needs as much love as it can get, and some of the best ways to spread the love is just by loving you.
Single or not, just love on this day. That's what's important.