How long does it take to learn guitar?
When I am asked the question, "How long does it take to learn guitar?", my out loud answer is, "Anywhere from one day to one year."
My inside-the-head answer, however, is, "Well, that depends."
There is one factor that weighs more heavily than all the others when it comes to how fast we learn guitar: How many guitar-playing friends and professionals do you know personally? The higher the number of people you know, the faster you'll learn guitar. How does this work?
The more people you know, the better the chances that they will start to want to play music with you. That's a pressure that you want. The more guitarists you know, the more likely you'll have support when you need it. The more guitarists that you know, the more you'll want to hang around and play music with them.
Let's say you agree with this idea but don't know where to start finding guitar-playing friends. That's easy: Find a guitar teacher first.
Try finding a guitar teacher; they're well-connected.
Guitar teachers make a living teaching the shortcut they know to learning guitar. Curriculums aside, guitar teachers can support you when you're feeling down about learning. Many, but not all, guitar teachers are supportive and helpful when the chips are down. That, and they tend to be connected. You can ask a guitar teacher for names of students who are at a similar level as you.
I think it's possible to learn guitar all on your own. The difficulty of this task is magnified however when a beginner won't reach out to find other like-minded people. Many beginners make the mistake of trying to learn completely in isolation. Many people who do online lessons won't even bother to join an online guitar community. Not only is this a tad lonely, but there is no support for when they have bad practicing days (and they do happen from time-to-time).
If you want to take a long time to learn guitar, if you want to make it more difficult for yourself, seek no friends online or in person, and certainly take no guitar lessons with a teacher who can be there for you when things get dicey. If you don't have the support you need, someone to believe in you like a guitar teacher or a community of like-minded peeps, it will take you a little bit longer to learn. Just consider it: friends can really help.