Japanese films don't handle love quite the same way that Western films do. No, there wasn't an explicit statement of "I love you" because Cloud and Tifa are not that open, but there was definetely a statement of "It will be alright now, because I have you." - Case of Tifa on Cloud's part. Tifa scolding Cloud in the movie as a wife would, ect. really, what would a grand sweeping statement of love prove? That wasn't Cloud's dilemna in the movie, as they are already passed this stage.
Like I said in another topic: "Many take Cloud's lack of audacious romantic impulses (think Hollywood) as ignorance of Tifa's feelings and/or no romantic interest in Ti. They forget that Cloud just doesn't have that bold, spontaneous kind of personality (kind of like Zack): if this applies to general social situations, it should apply to romantic situations as well. Like I said before - Cloud's awkward and reserved. His idea of romance and "making a move" is subtle and timid as opposed to grand and bold.
Instead of saying "I love you", he says: "Tender memories, secret wish.. noone can ever know.. it's your attitude that counts... it will be alright this time.. because you're with me.. that's how it will be, starting from tomorrow". Etcetera.
On a more basic level; Cloud was plagued by a terminal illess, ridden with guilt, and there were evil silver-haired pretty boys running around in AC. It's not like he could drop everything and go get hot and heavy with Ti during the movie. If he feels like a complete failure, how the hell could he perform in bed?"
Besides; the masters behind the movie state everything that you would need to know about their relationship in the Reunion Files.
"Although there's a lot to Tifa's character, she's actually very much like any other woman who's been left by a man. The director, Nomura, said he wanted me to make sure she wasn't a clingy woman, but to portray her as though she'd been hurt emotionally in a way that others around her cannot easily detect. But Tifa has expressed her feelings plainly to Cloud a number of times." - Nojima
"Tifa is a strong woman. She doesn't like what Cloud is doing, but instead of lecturing him about every little thing, she's been waiting for him to realize himself what his actions are doing. She's remarkably strong, not only emotionally, but physically as well. I think that using words to help Cloud lead to his own conclusions, instead of constant lecture, is a defining quality of Tifa's personality." - Nomura
"After establising the essence of Tifa's 3D model quite quickly, we had a hard time agreeing on the fine details. At times we wanted her to look stricter, while at other times we wanted a bit more compassion in her eyes. But then we thought she wouldn't balance well with Cloud's character. This sort of thing went on and on, but when Ms. Ito was selected as a voice actor for Tifa, we took alot of traits from her and blended them into Tifa's final appearance." - Nojima
"There are many dimensions to Tifa's character. She's like a mother, a sweetheart, and a close ally in battle." - Nomura
When translated to English, the context of "sweetheart" was kind of lost, because in the English language 'sweetheart' can be used in two ways: Romantic partner, or sweetheart as in 'nice person'. Like, "Oh, honey, you're thuch a sweetheart!"
But when refferring back to the actual kanji, it's the former.
Marlene is the daughter of Barret, who is actually the biological daughter of Barret's deceased friend from Corel, Dyne. (But he dies in the game). Dyne's dying wish is that Barret makes sure Marlene is safe. But from the start of the game Barret is already introduced as Marlene's daughter, and because Tifa is the only mother figure that Marlene has ever had in her life (besides Elmyra, but she was only watching over her) and because Tifa has known Marlene almost half of her life ever since Tifa joined AVALANCHE, she becomes Marlene's mother (but she's NOT Barret's wife; eww) and refers to her as a daughter when people ask.
Barret is Marlene's father
Tifa is Marlene's mother
Tifa is Denzel's mother
Cloud is Denzel's hero figure/father
Cloud + Tifa are together
... it may seem like a complicated family at first, but it really isn't.
She's a nice person. Anywhoo even if Tifa and Cloud are not in love, they were friends since childhood and I think it's close enaugh. Cloud listened to Tifa and became a hero yet again 
. as far as cloud's feelings i'm all over the place cause square represents him like he doesn't have feelings for aeris or tifa. and the one that he comes closest to showing feelings for is aeris, fore example when she dies he says to sephiroth "what about us?!" and her death clearly taps into emotions we had never seen cloud show before. 
coooool)
Also, that line was just to show that Cloud was obviously in some sort of distress and it was affecting the people around him as well. Tifa would be particularly affected by his behavior because of her feelings for him. Please try to consider her frustration as she is trying to help him the best she can and yet he simply puts more distance between each other. As he is with everyone else. 
