The most important thing to tell your attorney is EVERYTHING. Your attorney is your advocate and needs all of the information to help you.
1) I want a divorce.
2) I think my spouse does not declare all of his/her income, and I can prove it.
3) I can /can not afford to live on my own, and I want him/her out.
4) We have children (and the ages of the children). I am (or am not) the primary caretaker of the children.
5) If a parent has a drug or alcohol problem (past or present).