Taj Mahal A symbole of Love or what???

We know Taj Mahal as Symbol of Love. But the other lesser known facts.

1) Mumtaz was Shahjahan's 4th wife, out of his 7 wives.

2) Shahjahan killed Mumtaz's Husband to marry her.

3) Mumtaz died in her 14th delivery.

4) He then married Mumtaz's sister.

5) Question arises where the Hell LOVE is ??