It can be hard to let go of people that no longer serve us, because we feel we need stay friends. But I have a secret for you, you don't need to force things that aren't good for your mental health just because you think someone somewhere thinks you should. 

If you are in a relationship that isn't bringing you joy, serving your purpose, and/or giving you positive feelings, it is time to let it go. Set it free, kick it to the curb. However you want to say it. 

It is okay to end relationships because they don't fit. 

It is okay to walk away from friendships that are causing more harm than good. 

You don't owe people and explanation. 

You are putting your needs first, which we should all be doing anyway. 

Just because you've known someone for x amount of time, doesn't mean you need to continue feeding a toxic relationship, there isn't an expiration date on toxicity. It isn't like if you stay friends with that person, or in a relationship with them, after a set amount of time thing will go from toxic to sunshine and rainbows. That isn't how it works.