A man who is in love with you treats you nicely. He respects your opinion. He appreciates your presence in his life and tries hard to please you and build a strong bond.
On the other hand, bad partners usually do the following:
1. They prioritize destructive habits
A man who loves you will never put his addiction to alcohol or drugs before you. He will understand that it is destructive for you too since you will keep struggling and wasting your time trying to help him out. The longer you stay together, the worse this situation will be. You will feel more and more attached to the person who is dragging you down. Instead of helping him, you will ruin your own life.