Do you think the final bench scene was real?

I've seen a fan theory that states that the last bench scene was imagined by Tom, purely to get some closure from Summer, and I do think this could be plausable.

Summer had moved on from Tom. In her mind, Tom was nothing more than a friend. She knew friends can grow apart, and with Summer being the way she is, I imagine she could live her life perfectly well being married and believing Tom was still her friend - even if she was completely oblivious to his sadness (the last time they would have met before the bench scene would have been the party).

I also think that Tom could just have easily have figmented this. He had managed to turn his life around, becoming a successful architect, and though he had almost completely moved on from Summer, he just couldn't carry on without speaking to Summer one last time. By speaking to her, Tom felt like they had finally solidified their relationship as friends, and that they would share no mutual dislike for one another.

What do you think? Do you think that the scene was imagined by Tom?