Experts say the way people's brains work means you can become addicted to your partner in the same way you could be hooked on drugs or food.
If you are infatuated with your partner you could develop a dependency which has knock-on effects on your mental health, your job and your friends and family.
Dr. Femke Buisman-Pijlman, an addiction researcher at Australia's University of Adelaide, and author and counsellor Margaret Paul, PhD, have come up with 19 signs that you could be unhealthily attached to your other half.
'We can get addicted to people just as we can to alcohol or food,' says Paul.
'It's a form of self-abandonment where you use another person to avoid responsibility for your feelings.'
In the list written for Cosmopolitan, Dr Buisman-Pjilman adds: 'When you [first] fall in love, you can feel ecstatic like with initial drug or alcohol use.
'When the thrill of new love subsides, you could be left with a psychological dependence where you think you need the other person.'
Here are the experts' 19 signs you should be worried about your relationship:
You want to be with them so much it invades your own life
You annoy your friends by taking your partner everywhere, and spend time with them when you should be doing more important things.
Dr. Buisman-Pijlman says: 'Addiction is not about really enjoying something, but being unable to stop something that gives some pleasures but many problems.'
Your sex life gets in the way of the day-to-day
If you're regularly skipping work to have sex, having it in inappropriate places or at bad times, or it's taking up hours of your day, it could be unhealthy.
You can't control your desire to see or talk to them
If you set yourself rules about when you want to have contact with your partner but you can't stick to them, you might be out of control.
You spend all your money on them
It can be nice to give a gift every now and then, or help out with the bills, but you could be dependent if you keep buying your partner presents or get into debt because of them.
You can't be happy without them
Spending time with your partner should be a joy but you must be able to have fun when they're not around, too.
If you don't have other people or things in your life which make you happy you run the risk of becoming reliant.
You're scared to spend time on your own
You might be dependent if you feel uncomfortable or anxious when you're without your partner, for example when you go to bed at night.
You don't enjoy things you do apart
You should be able to enjoy time alone with your friends so they can do the same with theirs, without being too desperate to be back together.
If you can't stop texting them when you're out without them your relationship might be unhealthy.
You openly panic when you think of losing them
If you bump into their ex and you start to get angry or pick a fight because you think they're still interested, you could be jealous and irrational.
You need their approval
You shouldn't get too upset if they don't like your new shoes.
You start arguments just to get attention
If you often pick fights about petty things you might just be desperate for their attention, which puts strain on both of you.
You feel high when you're around them, but low when you're not
If you feel sort of drunk with happiness when you're together and devastated when you're apart, you could be addicted to them.
You try to calculate how much they love you by their actions
You could be obsessed if you scrutinise everything they do from their body language to the gifts they give and things you do together.
You shouldn't agonise over trying to gauge how much they love you.
You can't cope when they're away for work
If you stop caring and don't want to do anything if they go on a work trip, you need to take charge of your own happiness.
Likewise, you can't cope when they're away with friends
If they go on a weekend away with their friends you should be able to entertain yourself.
Feeling upset or angry that they'd rather be with their friends than you could be a sign that you're too dependent.
You use sex to try and make them love you more
If you force yourself to have sex with them to try and make them like you more, even though you're not in the mood, you could be overdoing it.
Sex shouldn't be used to buy their love, it should be something you both enjoy.
You don't do other important things because you're always together
If the housework doesn't get done and you don't see your friends or phone your parents, you could be spending too much time together.
It's important to keep normal life going outside the relationship.
You only enjoy being with them
If you used to enjoy spending time with friends and family but now you only want to be with your partner, the relationship could be damaging your social circle in the long term.
You're bad at your job because of them
If you don't get your work done because you're too busy texting them or checking your phone to see what they're up to, you need to take a step back.
You feel like your life would be meaningless without them
You need to love yourself, too.
More about: relationship