Jealousy is a common human virtue. But when it comes to our relationship, this one thing is enough to ruin any relationship. And I'm saying any because I'm not only talking about love relationship but every other kind of relationship.
Jealousy is not helpful in any way but sometimes we can't avoid it. But one thing we should remind ourselves that we shouldn't make any place for it in our relationships. Just think about if you become jealous of your sibling's success, or the way they look, how awful your life would be. And this same would happen to any other relationship.
One of the common things about relationships is caring, sharing, dependence, venting, mental support, etc. Jealousy just takes away all of this. Because when we start to feel jealous about the other party, we usually avoid maintaining any deep connection with them. This is the most harmful thing that comes from jealousy.
When you feel jealous about anyone, ask yourself why you are feeling this way. Most of the time it's not them but it happens because of our personal problem, self-esteem issues, and more. So instead of avoiding that person, deal with your personal problems.
And, if you feel like the other person feels jealous about you; then before cutting the relationship off try to help them to solve it.
I know it's hard. But not harder than breaking up with someone. Jealousy makes any kind of relationship bitter. So before it ruins your life, try to solve it out. Try different ways to work on your self-esteem, relationship issues.