It’s always nice to spend time with people you enjoy being around, but sometimes we forget that it can be nice to do stuff alone. For me, it's refreshing to experience common things by myself. Doing things by yourself offers the opportunity to learn about yourself, become more confident, and most importantly, realize that you don't need other people to enjoy living your life. Here are my recommendations for things that are perhaps even more enjoyable to do alone.
Riddle me this, why do some people think it's weird if someone sees a movie by themselves? Out of all the things someone should be allowed to do by themselves, without question, it should be seeing a movie in a theater which requires you to be quiet and sit still for two hours. If there's a movie out that you want to see but no one is willing or able to see it with you, go! If you do this already, then you know how fun it is to see a movie alone and give it your undivided attention.
This can be fun even if you're shy or not good at socializing. When you attend a public event such as a festival, concert, play, outdoor movie, etc. there is no reason to feel intimidated or even feel pressured to socialize. You can just go to enjoy the entertainment or whatever is being offered. Apply this to literally any time you go to something alone.
Above other types of shopping, thrift shopping is the most fun to do by yourself. You can spend as much time as you want to rummage through a bin of CDs or whatever want without something nagging you to hurry up. You can easily lose hours in a thrift store, especially if you're alone and can take your sweet time.
Driving to nowhere particular is different than your daily commute to work, school, the grocery store, etc. If you like to drive around and listen to music and enjoy the scenery, do it alone sometimes. Take back roads, go out of your way. When you drive alone, no one can argue about your choice of music or your driving or stop you from pulling over to take pictures of interesting things. Also, this is a good time to think. Think through whatever has been bothering you, cry, talk out loud, do whatever because no one is there to criticize.
I always prefer going to bookstores alone because when I'm with someone else I get distracted and end up parting ways with them anyways. It's nice to browse and read bits and pieces from books that catch your eye. Not to mention, libraries are better to go to as well. Spend however long you want in there reading or browsing.
Museums are so fun to visit by yourself because there's not really anything to do but ponder upon exhibits and read. Like libraries, you just browse around until something grabs your attention. You may even be surprised at all much more you appreciate the art and/or exhibits when you are alone.
I hope you all take the chance to do some stuff alone this summer. Everything on this list can be enjoyed with good company, but sometimes it's just nice to do stuff alone. It does you good!