Yes, almost every day of my life until I started connecting with people on the internet who felt and thought like I do.
I can't say what the cause in your case but in mine I was left out because how I saw the world and how I thought people should be treated just did not fit in with the common elements in my family or with many who were supposed to be friends. I was always at odds on just about everything.
I was also left out, or as often opted out, of conversations because what "they" chose to talk about was so totaly freakin boring to me I wanted to scream. I'm not someone who has to be serious all the time and get into heavy rap sessions although I do really enjoy them but give me a break, how long can you talk about getting your hair done, going shopping and what you saw on some dumb reality show? Well evidently some people can talk about that for days or weeks on end, saying the same crap over and over and over while I run in the other direction.
I like to talk about movies I've seen, and I'll watch almost anything...books I've read, and I'll read almost anything except romance...ideas such as why our school systems spend more money then any other in the world but our students rate somewhere around 20th when compared to other countries..or why after all this time there is still a race issue, why this country ignores conditions on the reservations where many are in dire need...the list is endless
Maybe you just need to figure out what you care about and then find people like yourself, the net is a huge blessing in that way

This is my first time I've posted so let me give a short rundown.
BW/WM couple married for about 4 years. Our families didn't adjust to our marriage so now we don't deal with them. I do remember what it like being around them. It went something like this:

When I visited my MIL I would feel like I was being talked at not talked to. On the surface it seems like I was more than welcome to join the conversations, but in the end it felt like an empty gesture. I would try to say something only for it be glossed over. My husband would be chatting it up. No issues. As soon as I opened my mouth my MIL and SIL would give a half-hearted smile and start taking about something else.

At one family function I was ignored all together and when my husband spoke about the treatment I was receiving he was then ignored.

So in their own way they'd made it clear that they accepted the relationship, but they wouldn't accept me. It didn't matter what the reason was ( race, culture, religious etc.). After a year and half I couldn't deal with it anymore. I'm glad my husband addressed the issue or we wouldn't be together now.

I don't know how long you've been dealing with this, but I can assume that its been going on long enough that you came here for honest opinions or perhaps advice.

You need to figure out whether this a passing phase or this is the way things will be for now on. You're already unhappy with the way things are right now imagine in the next six months or year? How will you feel then?

we have been together going on 9 years. it is just that at times i just feel that the conversations are just way out in left field. That they have no meaning. It seems that they make promises to each other that they never intend to keep. Like i stated i speak the language and i totally undersatnd even the jest of the jokes as i have been totally intergrated in this languages for years and years but i don't understand how they can take things so lightly. like Georgia said they take things so lightly. I tend to tke thing more seriously. i have more things to worry about than what sing is dateing who and who is wearing what. I tend to worry about the world today. I am a educated person and when i bring up something they tend to think in that they are still in their world and that they can take thing so lightly like they did there. Like the other day we almost got into an argument over a issue because i was talking about an issue that I know alot about and someone interject that they knew more. Sorry but I went to college for this and they never even complete a 5 grade education. I just shutup and said okay yeah you are so educated. After taht they continued to talk around me in their lil joke like language thinking I woudn't understand But I do. So I just listened watching the news. And they wonder why people look down on them. I have made it a point to educate myself

I understand. I'm sorry for the irreverent response to your original comment. You feel left out the reasons you stated.

You're educated - They're not.
You're more socially conscious - They're not.
You're don't assume you know everything. They do.

You stated that people look down on them. What does have to do with you feeling left out? It's obvious that your feelings of being "left out" are starting a take a negative turn.

I know it can be frustrating to deal with people who are not on same wavelength as you, but don't let eat you up from the inside. GeorgiaW is right. You need find people like yourself so your feelings on the matter can be put to rest.