Can someone with adhd still have a steady relationship?

Yes: If you have adhd behaviors that seriously thwart interpersonal relationships - consider an adhd group where you can get reality based feedback and improve your social skills.

ADHD Is NOT Destiny: Having adhd does not make you an insensitive, inconsiderate partner, parent, child. Some of the brightest, most energetic and fun people i've known had adhd. If your relationships are not as satisfying as you'd like them to be, consider exploring the obstacles you're running into, including problematic patterns of behavior that leave those close to you feeling disappointed or disconnected from you.