He lived in England and she lived in the Atlanta area. But that was only temporary for Matthew Willson and Katherine Shepard.

The two had recently celebrated their third anniversary as a couple, and a constant topic of conversation was the future. Once Shepard finished her doctorate degree, there was talk of marriage and living in the same city once again. Late last week, Willson had flown to Atlanta to spend three months with the love of his life.

“He was so happy to be here and be able to spend time with Katherine,” Willson’s sister, Kate, told The Atlanta Journal-Constitution late Friday.

But the visit lasted only hours before Willson was killed. Investigators believe a bullet fired from a neighboring apartment complex blasted into Shepard’s bedroom early last Sunday, hitting her boyfriend in the head.

“It’s impossible to comprehend how it is even true,” Kate Willson said.

Days after Matthew Willson’s death, those closest to him struggled to understand how the 31-year-old could have been asleep one minute and struggling to breathe the next.

“This incident appears to be a random act involving individuals participating in the reckless discharge of firearm(s) which led to the tragic death of Dr. Willson,” Brookhaven police said in an emailed statement.

Around 2 a.m. Sunday, multiple people called 911 to report hearing shots in a complex in the 3600 block of Buford Highway, Sgt. Jake Kissel said. While officers checked the area, another 911 caller reported a man had been shot inside an apartment in the 3100 block of Clairmont Road.

It was Matthew Willson, an astrophysicist who had met Shepard while completing post-doctoral work at Georgia State University, where she was also a student. Willson, who lived in Chertsey, Surrey, England, was currently completing additional post-doctoral work, Shepard said.

Early Sunday, Willson had already gone to bed, still jet-lagged from his flight. Shepard was up late and heard several gunshots outside.

“He woke up to gunshots,” Shepard said. “I heard them and I had just turned off the light.”

The two heard several gunshots and then a pause. More shots and then another pause. Shepard tried to look out the window to see if she could tell where the shots were fired. She noticed Matthew sit up.

“Then the bullet came through,” she said. “Then I heard his breathing change.”

And Shepard saw the blood and realized Matthew had been shot in the head. He was taken to the hospital but did not survive.

“The doctors and I have talked a lot about it,” Shepard said. “We’re pretty sure he was gone on impact.”

Now, Shepard says she is struggling to make sense of her boyfriend’s death. Investigators have not yet found those responsible for firing the gunshots. Meanwhile, Willson’s family is planning memorial services both in Atlanta and in England.

“The smallest thing we could ask for is that whoever did is held accountable,” Shepard said.

Anyone with information on the shooting is asked to call Brookhaven police at 404-637-0636 or tips can be submitted anonymously to Crime Stoppers by calling 404-577-TIPS (8477).