[{_id:"blabla",userName:"blablabla",interactedUsers:["blabla2","blabla3"]},{_id:"blabla2",userName:"blablabla2",interactedUsers:["blabla"]},{_id:"blabla3",userName:"blablabla3",interactedUsers:["blabla"]},{_id:"blabla4",userName:"blablabla4",interactedUsers:["blabla5"]},{_id:"blabla5",userName:"blablabla5",interactedUsers:["blabla4"]},]

db.collection.aggregate([{$addFields:{"ignore":"blabla"}},{$lookup:{from:"collection",localField:"ignore",foreignField:"_id",as:"ignore"}},{$set:{ignore:{$arrayElemAt:["$ignore",0]}}},{"$match":{$expr:{$not:{$in:["$_id","$ignore.interactedUsers"]}}}},{$unset:"ignore"},{"$match":{$expr:{$ne:["$_id","blabla"]}}},])