After further testing I have determined that the VPN tunnel did not fail.
I created a new tunnel to a different location.
Connected the ipsec tunnel between the two locations and did a test ping to the pfsense server private ip address, (192.168.10.3) it works.
Connected to the another host on the VPC network at DO and set its default gateway to 192.168.10.3 and able to ping it from the remote host of 192.168.0.2. The constant ping has been running for 2 hours now.
But I did determine that when the initial site-to-site tunnel was connected, I lost communications to the public ip address of the pfsense host at DO from my local computer. (not part of the current VPN tunnel) And from the local VPN site, I cannot open the private ip address of the pfsense host through the vpn tunnel. https://192.168.10.3. But I can ping the host of 192.168.10.3
I have a setting wrong someplace. Any suggestions?