I had a really hard time while I was married because I had little ones at home and couldn't go out, but my ex-husband wasn't good company. It was a site much like this one that got me through.
Sites like Meetup are pretty good too. With that, you can find groups of people who have interests similar to yours and attend events. Sometimes it's easier to go out with a whole group because then you're not dependent on one or two people, so even if you don't jive with some of them, you may find a couple you really get along with or find the activity to be entertaining enough that you don't feel so alone.
Hmm, I don't know. I feel bad for lonely people but but then sometimes I'm just too shy myself to reach out to that lonely person and then I feel worse about myself for being shy and I regret it later but since I've had kids I've felt a lot more lonely but no matter how much time my husband spends with me I still have that feeling even if he talks with me all day long.