Step1
1. If he cheats with you, he'll cheat on you!
Like many, you may find that dating an already "taken" or married man is exciting; the intrigue and taboo add to the attraction. You may think "she's not right for him, otherwise why would he be with me?", or "he can't be truly serious about her if he's willing to be with me". While these arguments may help you justify your actions to yourself, you need to take a hard look at his actions. We all want to be special (or in this case, MORE special than the other woman), but how special is he if he's willing to betray what he already has with someone else. Remember...if he cheats with you, eventually he WILL cheat on you.
Step2
2. If you compromise yourself (morally, ethically, spiritually) for him.
Do you find yourself making excuses for his actions and/or going along with things you feel are just not "you"? Have you allowed things to happen (sexually, financially, with your children and/or family) that you would not have allowed but to please or appease him? All relationships require give and take by both parties, but you should never feel that you have to compromise your core being for the sacrifice of another person.
Step3
3. If you don't put him above all else, he threatens to leave.
Of course your partner should be a very important part of your life. However, if he threatens to end the relationship if you don't put his wants and needs first, he is not the one for you.
Step4
4. If you feel forced to behave in ways that are not natural or comfortable to you.
This issue is mostly about sex, but can extend to other areas of your life as well. It is likely that he will try to make you feel like there is something wrong with you, or that you don't love him if you don't comply to his wishes. There is nothing wrong with you: if he has requested (or even coerced) you into doing things in bed (or otherwise) that make you uncomfortable or even frightened, he is most certainly not Mr. Right.
Step5
5. If he wants you to change your appearance.
When women meet someone new, they might lose weight or start to take more care in their general appearance. It is natural to want to be attractive to your partner, but if he insists on radical changes (cutting or growing your hair, or wearing it in a certain style, changing what type of clothing you wear, etc.) so that you'll "still turn him on" or "not embarrass" him, then it's time to walk away.
Step6
6. If he tries to isolate you from your friends and/or family.
He may say that he only wants you to himself "for now" and would be "willing" to participate and/or share you with others at a later date. It can be flattering to feel as though he "wants you all to himself" or doesn't want to "share" you with anyone else, but this is a very unhealthy sign.
Step7
7. If you have given up time with your child/children to spend it with him.
It is a difficult thing for single mothers to find the time for a romantic relationship. While this is true, it does not give any man the right to ask (or require) that you forsake your child for him. This is not only a sign that he doesn't understand the importance of your role as a mother, but it sets a bad example for your child.