Salam Lulu, 

Thank you for your question. 

What is spirituality if it’s not deep faith and connection with the Creator/Source of the spirit?

We know from the hadith that iman (sincere belief) is:

[…] to believe in Allah, His angels, His Books, His Messengers, and the Last Day, and that you believe in preordainment (destiny), its bad and good consequences. [Muslim]

How can we be “spiritual” (focused on the spirit/soul) if you don’t have deep knowledge and constant connection with the Creator of your spirit, Allah Almighty? As you can see for the hadith, iman involves matters concerned with deep knowledge, deep belief, and connection with the unseen and this requires true, firm, and unwavering iman.

I hope this makes things clearer. 

Please keep in touch.

Salam.

Please check out these links for more info. 

Lived Spirituality: What is Ihsan?

Heart & its Connection with God