Air carrier Captain reported loss of aircraft control due to severe turbulence while conducting a go-around from wind shear encounter. On second approach attempt; flight crew executed a missed approach and diverted.

Narrative

On final approach to Runway XXL; I assumed the role of PF just above 1000ft. after ZZZ Tower replayed to us a PIREP of an aircraft that landed before us reporting dramatic changes in wind during its approach; approximately 180 at 35 kts at 1000 ft.; then 180 at 9 [kts] landing. I noted winds of approximately 45kts from 180 but starting to decrease as we descended during the approach. I disconnected the autopilot at 1000ft. and at around 500ft. we received an oral windshear caution and associated WINDSHEAR FMA's (Flight Mode Annunciator). We immediately began to experience heavy; then shortly thereafter severe turbulence as airspeed was plus or minus 20 kts from commanded airspeed while we performed the escape maneuver. The aircraft responded well the power addition and at no point did I feel ground contact was likely so I did not feel it necessary to power through the FADEC (Full Authority Digital Electronic Control) bar. As we climbed to 3000 ft. we were vectored West so as to not interfere with traffic that may have been conducting parallel approaches to [Runway] XYR. Unfortunately; that caused us to fly into the squall line where the intensity of the turbulence and sound of heavy rain was very intense. I tried to connect the autopilot but it would not stay connected due to the severe turbulence which I would describe as at least double or triple the worst turbulence I had ever experienced up to this point in my flying career. Despite my best attempts to hold altitude we were +/- approx 200-300ft. off assigned (and so requested a block altitude). Even maintaining angle of bank/heading was difficult and airspeed control was almost impossible as it was rapidly jumping up and down 20-30 kts. The green airspeed predictor indicator was alternately pegged off either the top or the bottom of the airspeed tape on the PFD (Primary Flight Display). Even though we were above slat retract speed with a positive vector and the WINDSHEAR guidance had already terminated; I had elected to delay retracting the slats which was helpful as we decelerated back below Sr (Reference Stall Speed) speed a few times (though only briefly). After we were well south of the squall line we discussed making another attempt. Since we didn't really experience the severe turbulence until being vectored west on the go around; we decided that if we could coordinate a vector East (in the direction of our alternate ZZZ1) in the event of a MA (Missed Approach); we would try again. As we descended through about 1500 ft. we went IMC and I once again noted the strong tailwind begin to rapidly decrease. Rather than risk another windshear event; I elected to execute a normal missed approach with the autopilot still connected. The MA and divert to ZZZ1 was uneventful.Windshear associated with frontal passage at destination airport.I don't know that this event could have been avoided without the company having delayed the recovery by some hours to allow the line of forecast storms to pass through. The vector we received to the West (on the MA) into the weather was the reason we encountered most of the severe turbulence; but we quickly requested a turn further to the south which ATC issued. I will add that the windshear training we receive during training is quite accurate in simulating the effects of the turbulence and driving home the importance of always being ready to execute an escape maneuver when weather conditions warrant.