But it will never take away the 'life-lasting memories' he and his team-mates created along the way to stand one win from a Wembley final.
USP could hardly have been dealt a crueller blow, with their incredible run coming to an end with a 4-3 penalty shoot-out loss to Hellenic League Premier Division Binfield.
That added to the earlier anguish of Liam Ferdinand - step 3 player prior to the December lockdown - cancelling out James Franklyn's first-half opener 10 minutes from time.
Yet, once the dust settles and the USP squad come to terms with such a heart-rending loss, Glen insists the FA Vase journey is one everyone associated with the club can reflect on with immense pride.
It's a period that the 24-year-old will look back on with fondness for many years to come.
Glen – who was voted his side’s man of the match against Binfield by boss Glenn Turnbull - said: 'We’ve gone from having the highest of highs the past few weeks, every game being a cup final, then it can end as quick as it started.
‘You’ve just got to enjoy the ride as it goes.
'Ultimately, it was always going to end at some point - unfortunately it wasn’t the success we wanted - but we can be satisfied with what we’ve done over the course of it (the run).
‘It’s tough to take obviously, but we’re best mates pretty much and everyone, to a man, gave everything they had.
‘That’s why we can be satisfied, it’s not like we didn’t give everything, it’s not like we didn’t play our way - it was just a case of the final hurdle.
‘You break it down, we were 90 minutes from Wembley, then 45 minutes and then almost 10 minutes away.
‘We were then one penalty away from being a penalty away from going through.
‘I’m proud of the club, I’m proud of the people and the boys at the club, I’m proud of the management and the squad.
‘I go on Twitter every day, buying the paper every day and there’s something about United Services which is unbelievable.
‘It’s almost impossible to be doing any work on a Monday to Friday. The group chat has been going mental every day.
‘You can look at it two ways, you can either saviour the moment and not let it affect you; for me, it was a case of embracing it and enjoying the moment.
‘It’s not just what we’ve achieved - getting to the semi-final of a national competition is an unbelievable achievement - but it’s the memories you’re going to keep.
‘I know it’s cliché but the memories will last a lifetime because you’ll look back in time - it’ll take a couple of months probably because it will hurt - but we’ve got to try to use this as a base to push on.'
USP won plenty of admirers as they came through seven FA Vase rounds to reach the semi-final stage.
They defeated six higher division clubs in the run, which started back in October with a second round qualifying victory at AFC Portchester.
Glen revealed he had to raise a smile on the pitch during the semi-final seeing the cameras in the stands at the Victory Stadium and assembled press - something very different from Wessex League 1 games.
He added: ‘The overall feeling will be pride. I’ve received countless messages saying how much they enjoyed supporting.
‘I’ve had people messaging from my time in America who watched the game and they said they enjoyed it.
‘I remember someone put in the group chat that it had been 210 days since the greatest win in USP’s history (winning at AFC Portchester) but we’ve gone through a few rounds since.
‘It now feels miniscule (beating Portchester) in terms of what we have achieved.
‘Going down to Tavistock and winning, beating Millbrook in December, beating Christchurch on penalties, who are the best in the Wessex over the past couple of seasons.
‘I remember being on the pitch and just smiling thinking, ‘there’s seven or eight cameras here at a ground where I’ve played and there’s been not a soul in the stadium’.