Dating "older" isn't 4-5 years. Claiming that you're dating "older" with that age gap is just showing your inexperience in the dating world. Dating "older" is a large age gap like 10+ years. Even 10 years isn't that awful, but anything beyond that is really a huge difference in socio-economical status.
Sorry, but age does matter in the long-term. If you want the experience of an older girl to fool around with and experiment, then yes, it doesn't matter because it's just a fling, but for the long-term, it generally doesn't work out.
But I can certainly appreciate the young, idealistic thoughts. I was there once

, and I understand how the inexperienced can have this type of wishful thinking.
Not to be a party pooper, but a month older would be dating, 'older' and a month younger would be dating, 'younger'. It's not inexperience, to say your dating 'older', if there 4-5 years older. It's merely using the word older... Your setting your own rules and calling people inexperienced because they don't follow them.
but anyway,
I want to hear more about why you think it won't work? So far you've pushed your view that it won't work as opinionated fact. IT WONT WORK, simple. So tell me why in your eyes, you think it won't work?
Is it because of looks? Because sorry I'm not that shallow.
Is it because of differences? We like the same music, we like the same programs, doing the same things etc... she likes wigan pier, I like wigan pier. How crazy.
My eldest brother is older then my partner.
My mother and father are 11 years apart and they have been happily together now for 35years and married for 29 of them.
My partners mother and father are 10 years apart and they are happily married. Her mother adores me.
The other night we had a get together, me and one of her friends husbands, who is in his 30s got on like a house on fire, had a 3 hour chat on philosophy and I.T.
Children? I can't have children and she already has children and swears she doesn't want more, even when with me she admits, I would make the perfect Dad compared to the father of her children.
Our life and relationship is no different to any others and the only thing which will change over the years is her looks and her going through the menopause. We are ready for the menopause and I couldn't care whether she grows old and saggy, I just want her there, to talk to, to be with. If anything, the fact she's older and I'm younger makes our relationship all that more special. Because through all society's judgements and hidden rules, our relationship stays stronger.
She told me she loved me first... we aren't just a couple. We are best friends.
So tell me, why are you so pessimistic and adamant it won't work? I'm not naive to think its 100%. But I'm not so pessimistic to damn the whole concept.
Is there an experience in your youth which has set you against such relationships?
If its merely based on society's opinions, then It isn't relevant. I care not for society and there woolly backs.