const prepareString = (text) => text.split(' ').join('').split('');

const flames = (name1, name2) => {
  const flames = ['FRIENDS', 'LOVERS', 'ANGRY', 'MARRIED', 'ENEMIES', 'SOULMATES'];

  const name1arr = (name1.length < name2.length) ? prepareString(name1) : prepareString(name2);
  let nameToCompare = (name1.length < name2.length) ? name2 : name1;

  const matches = [];
  name1arr.forEach(x => {
    const indexMatch = nameToCompare.indexOf(x);

    if (indexMatch > -1) {
      matches.push(x);
      nameToCompare = nameToCompare.replace(x, '$');
    }
  });
  return {
    matches,
    flames: flames[(matches.length-1) % 6]
  };
}
const result = flames('m a r k h u g h n e ri', 'm a r k h u g h n e r i')
console.log(result);
// { matches: [ 'm', 'a', 'r', 'k', 'h', 'u', 'g', 'h', 'n', 'e', 'r', 'i' ],
//   flames: 'SOULMATES' }