Atheist celebrations are not that much different than any other celebrations. First, there aren't many 'coming of age' celebrations left in our modern world, which I feel is fine. Both the religious and the secular experience things such as first dates, graduation from high school, moving out of their parent's house, renting their first place, getting a real job, etc. These are all secular 'coming of age' events.

Birthdays are always secular, as far as I can see. No one ever really mentions anything religious at birthday parties or events, so I feel like those are almost always secular.

Other major life events, births, deaths, weddings, etc, can all be celebrated in a secular way.

I have had to attend many church services and religious events for my work, and even that is fine with me. I am there to support another person, and if they choose to attend church, that is their choice in life. My attendance in the church or event is for their support only, and it is very easy to distinguish that. (I don't participate, but make it known to the person that they can participate as much as they would like.)

I think that if I can make going to a church service a secular event for myself, then anyone with a little imagination can do the same for any other life event!

One of the main drivers forces for atheists going to religious celebrations are, of course, family. As a participant, you don't really have any right to "take charge" and attempt to alter another's celebration. But, I don't think anyone should ever be pressured to make their own celebrations religious on account of family. Especially celebrations that are very important, like weddings. Just remember, it's your celebration, you do have a right to have it your way. And, if you're respectful of their ceremonies, they should be respectful of yours.

I bet I know what you're talking about.

A certain atheist we know, ahem, got married in a traditional religious ceremony and stood up before 'god' and all and basically let his nuts get tied into a little bow... I was not happy.

I am glad he is happy and all, and I really like the lady he got married to, BUT, I personally could never ask someone I loved to stand up in front of people and lie about their beliefs... Luckily, I don't have to do that!