I wrote this e-mail to a woman who sent an e-mail to a group discussing her worries about her daughter having enough friends. I sent this response:
I am sure you are going to get a lot of e-mails telling you to not worry. I disagree however. Being an introvert (I don't know if you're introverted or actually anxious about social situation) myself, I see that it is very difficult for my daughter to not have a lot of friends (a lot meaning around 5 or so). She dislikes homeschooling because of it. While we have homeschooled for three years, I cannot blow off her desire for friends like some other parents would recommend or trust that it will 'just happen'. We are homeschooling now because I want to assure that she has a strong academic foundation and I have not felt that sending her to school at this point (even if she wants it like mad) would be best for her.
It is wonderful that you understand your personality and are thinking about this in advance. I can offer some advice.
Go to groups. It doesn't matter if it's a weekly group or monthly. I hate dragging the kids out (I also have a young one and it's a lot of work to take the 18 month old out with the others) but I recognize that I NEED to do it for the kids. Go to park days.
Be prepared to drive distances (you'll hardly ever find things within 10 minutes of your home) but if you're willing to drive 1/2 an hour (my personal limit) or 45 minutes (I know parents who do up to an hour), you'll find the number of people your daughter (and you) can befriend will increase dramatically.
Go to classes or groups even if you're not sure that they will be interesting. This is actually a rule I DON'T follow--I do not like to spend a lot of time out of the house just to get out of the house. Since I'm homeschooling for academic reasons, I need seat time for the kids. But it is probably worth while to find one or two that you can live with even if they aren't exactly what you'd prefer for your daughter.
Be flexible! Friendships DON'T happen in clubs or classes or any structured activity. They happen during down time. If kids are staying after a class to play, then stay! Be prepared to stay after every event. If it looks like your daughter is getting along with someone or talks to someone, then even if the kids aren't staying, then be prepared to offer invites. If the class was before lunch, then ask if they'd like to go to a local McDonald's (hopefully that has a playscape). You can even just make a general announcement that you're heading to a nearby park to play for a while and hope to see others there.
You can join town activities, but the same rule holds for town activities. It's really hard to make friends when kids only see each other at structured activity. The structured activities should be seen as conduits through which to meet people for scheduling play dates, not the actual place where your daughter will make friends.
Hardest for me: get people's phone numbers and call them! I get phone numbers but rarely ever follow through on playdates. This is a detriment to my children and thus makes me unhappy, so I personally really need to work on this.
Not all homeschoolers are going to be good playmates for your child. Some homeschooled children really do have social issues--I've seen kids hit and behave inappropriately. Just because people are homeschooling doesn't mean they're parenting well or that their children are well-adjusted. Also, not all personalities mesh well, so not every decent kid you meet will be a good fit for yours. Going to a group where kids have been homeschooling together for a while can lead to your daughter getting the cold shoulder even if she is willing to put herself out there. Failure happens! It's disappointing, but she will get over it if she has other opportunities for success.
If you are having a hard time meeting people or finding a class/club that fits your schedule--START one! It could be a play group, a book club, a craft club, a sports club, a park day, a girls' club (that's what I did). Hosting something in your house involves a great deal of work--organizing the activities, having lots of kids over--usually leads to messes, having parents over means the house has to be clean (very hard for me though it does have a bonus that my house is cleaner than it would be), providing snacks, having strange kids using your bathroom (lids up, misses, pee on the seat), but you can allow kids to stay and play for as long as you like and you know that people who are willing to travel to your house are generally close enough for play dates. People you meet at places that are far away from your home could be an hour or more away.
The activities you read about in groups and the ones posted on-line are probably 1/2 to 1/4 of the activities going on for homeschoolers. Many homeschoolers organize activities and run classes or meetings without ever needing to invite the general population--they fill the classes through people they know personally. The ONLY way to find out about these opportunities is to go to the park days, clubs, and advertised classes and meet people. Expand your network!
It might seem daunting, but I hope those ideas help you right from the start. I had to learn them slowly over the last few years.