1. Remember, just because you want something (or someone) doesn’t mean it’s good for you. You can’t give into every single temptation. You can’t impulsively do the first thing that pops into your head. Your actions have consequences. Before you make a decision, you need to think through what it would entail. You have to ask yourself whether it will be worth it in the end, whether the rewards outweigh the risks.
2. You’re better off on your own than stuck with the wrong person. Your loneliness might be messing with you right now, but you have to remember that you deserve the world. You shouldn’t settle for less, simply because you are bored. You don’t want to complicate your situation. You don’t want to put your heart through a storm. If you chase after someone you already know is bad for you, you might be happy for a short time — but it isn’t going to end well.
3. Remember, you are stronger than your temptation. You might have trouble ignoring this person. You might feel like you’re bound to break eventually so you might as well do it now. But that’s not true. If you can spend today without them, you can spend tomorrow without them. Take it one moment at a time. One breath at a time.
4. Remember, this isn’t the only person who will ever hold your heart. Right now, they might be the only one who gives you butterflies. They might be the only one who turns you on. They might be the only one you can picture in your future. But you are going to love again. You are going to find other partners who get you excited — and they are going to feel the same way about you. This isn’t your only shot at a relationship. There are plenty of other opportunities waiting for you, so don’t worry about missing out on love.
5. Remember why they’re such a bad idea. There must be a reason why this person is bad for you. If they have hurt you in the past, instead of focusing on the good things this person has done for you, think of the bad memories. Think of the times they have disappointed you. Think of the moments when you swore you never wanted to see them again. Instead of focusing on how much you want them, focus on how much better off you are without them.
6. Remember, your support system can be a big help. Instead of texting this person, text your friends. Instead of asking this person to come over, invite your friends over. Keep yourself busy. Distract yourself. Have fun without this person to prove to yourself you don’t need them in order to feel fulfilled. The less you think about them, the sooner you’ll get over them.
7. Remember, spending time on your own can be the best thing that ever happened to you. You don’t need someone else to validate you, to support you, to make you feel beautiful and worthwhile. You can do those things for yourself. 
Source: https://thoughtcatalog.com/january-nelson/2020/07/7-reminders-when-youre-tempted-to-chase-after-someone-bad-for-you/