I just don’t understand why it’s so hard

I fell pregnant without trying 4 years ago this month with my beautiful boy who is now 3, I have been trying for over 2 years to have baby number 2 and it just is not happening! I’m on cycle 2 of letrozole and once again negative. I’m 10 dpo today and no sign of a positive 😞 period due in 2 days. At this point I’ll try anything, is there any crazy things that worked for you?