the use of simply in a sentence

Another couple are ahead of me now, sitting on a park bench, huddled together against the brisk wind. As they stand up and walk towards the park gates I notice their companionship as well as love. Would Greg and I still be talking like we do now when we have been living together for a while? Perhaps, in time, we would simply run out of things to say to each other. Perhaps if we fight to maintain our own interests as well as establishing joint interests then we should still remain individuals within the relationship. It would be hard work but it would be fun too, wouldn’t it? I’ve fought hard to get where I am today and I’m proud of my success. We’d have to work hard to have a relationship we could both be proud of but it could be done—I’m sure of it.

1.
a. In a plain and unadorned way: dresses simply.
b. In an unambiguous way; clearly: explained the concept simply.
2. Not wisely or sensibly; foolishly.
3. Merely; only: It is simply a matter of time.
4. Absolutely; altogether: simply delicious.
5. Frankly; candidly: You are, quite simply, the best candidate for the job.