Good morning brother. May I ask what effects does said relationship have to us and our Gods? If they are affecting you personally I suggest you do a reflective protection of some kind. For example use algiz and sowilo rune. Then affirm: i am always protect from all forms of harm. All negativities and attacks against me are returned in full to the senders destroying them completely.
Curse less. Its not productive. Focus on spiritual advancement, maintain you daily meditations and yoga + physical work out and everything will be fine.
Now if you really want to break them up(not recommended) do workings on their aura to make them hate each other and break up on their own but that requires you have stronger aura than both of them otherwise the working might backfire on you which is why it's not recommended. Focus on you improvement instead