Each relationship defines sex in their own way and that is the way it should be. Don't let anyone else tell you what is or isn't acceptable for your relationship. You can and should talk to others and find out what works for them or what they think but you and your lover/lovers should decide what boundries you want in your relationships. There is nothing that says that those boundries could not change in the future. This question though should be worked out by a discussion with your partner though. Since you probably just came out of a religion that taught no tolerance when it comes to sexual and relationship matters I really think you and your partner should get some different viewpoints on the subject and decide for yourselves what type of relationship you want or can handle.
Just my 3 cents.
TimB