The money for the center is included in a Veterans Affairs and Housing and Urban Development appropriations bill, which at one point also cut $2 billion from veterans' healthcare services.
Simmons, who is chairman of the veterans health subcommittee and a Vietnam veteran, voted against the bill, much to the displeasure of the Republican leadership in Congress.
"Normally what that means is that everything else I had in that bill disappears," he said.
But as Town Council members and town staffers walked through the rooms of the new building, Simmons said they could be confident that the money will be coming to Enfield.
The House voted to approve it on Monday, and Simmons said he expects the Senate to do so in January.
Since the bill is a conference report, no amendments can be made, and a simple "up or down" vote on its contents is required.
"It will pass," Simmons said. "It's just a matter of time."
If the money does come through, it will join $400,000 in state money and a previous $150,000 federal grant that went toward construction of the $1.1 million facility. That means Enfield taxpayers contributed about $250,000 for the building.
That is an increasingly rare funding formula in a time when state and federal sources have been reluctant to spend as much in grants as they once did, according to Town Manager Scott Shanley.
After the ceremony, Simmons recalled during an interview in his Pearl Street congressional district office how the funding almost fell through.
In an April 4 letter to the chairman of the VA and HUD subcommittee, Simmons proposed allocating $600,000 for the Enfield center.
A few weeks later, Simmons and some other Republican legislators threatened to vote against the House of Representatives budget because it contained what they said was inadequate funding for veterans' healthcare.
Simmons said he believed after that dispute that the funding had been restored, but he said he was "shocked" shortly thereafter when the appropriations bill came through with $2 billion cut from it.
"I've been a Republican for about 17 years, and I'm proud of that," he said, leaning forward to hammer his point home. "I've been a Congressman for three years, and I'm proud of that. But I served my country in uniform for 37 years. I have to keep faith with my fellow veterans first and foremost because that's my whole life."
Simmons tried to amend the bill to include the funding, but the rules committee refused to allow it.
When he tried to speak against the bill from the floor of the house, he was again refused -- so he spoke from the Democratic side.
"It's a little unusual," he said. "In fact, it's very unusual."
In the end, 59 Republicans voted against the bill. According to an Army Times report from August, Simmons, along with five other Republicans who spoke against the bill, faced "punishment" for doing so.
The report said that in addition to denying funding for projects like the Family Resource Center, appropriations committee members threatened to use that money for Democratic projects instead, thereby garnering bipartisan support for the bill.
When the bill emerged from conference with the Senate version, though, both the $2 billion for veterans' healthcare and $225,000 for the Family Resource Center were included.
"I felt vindicated," Simmons said. "I was taken to the woodshed several times during that budget battle, but I think they respected my position."