Quote Originally Posted by impulse View Post
I will deffinately search about деепричастие. I did not know it. And I think it will increase my understanding of the Russian grammar.
Paul G. already mentioned it, too.
Shortly:
Деепричастие (verbal adverb) is used to express a "background" action where the "main" action is expressed by a normal verb. (What is "background" and what is "main" depends on the speaker's view).
There are two kinds of деепричастие:

1) imperfective (only derived from imperfective verbs). It expresses simultaneous actions:
Разговаривая по телефону, он жуёт жевачку. - He chews a chewing-gum while talking on the phone. "разговаривать" is an imperfective verb, "разговаривая" is a деепричастие.
Читая книгу, я думаю о своих проблемах. - I am thinking about my problems while reading a book. "читать" is an imperfective verb, "читая" is a деепричастие.
Сидя в кресле, он закурил сигарету. - He lit up a cigarette while sitting in the arm-chair. "сидеть" is an imperfective verb, "сидя" is a деепричастие.

2) perfective (only derived from perfective verbs). It expresses consequent actions:
Придя домой, я увидел своего друга. - Having come home, I saw my friend. Action one: Я пришёл домой. Action two: Я увидел своего друга. Action one is completed before action two. "прийти" is a perfective verb, "придя" is a деепричастие.
Сняв шляпу, он поздоровался со мной. - Having taken his hat off, he greeted me. Action one: Он снял шляпу. Action two: Он поздоровался со мной. Action one is completed before action two. "снять" is a perfective verb, "сняв" is a деепричастие.
Купив машину, я начал читать инструкцию. - Having bought the machine, I started reading the manual. Action one: Я купил машину. Action two: Я начал читать инструкцию. Action one is completed before action two. "купить" is a perfective verb, "купив" is a деепричастие.

A good news for you: деепричастие does not change! It has no conjugation forms, no gender, no tenses, no cases. There are just an imperfective version and a perfective version. Nothing else

In your example, "любя" is an imperfective деепричастие of the imperfective verb "любить" (to love). So, it means literally "while loving ...". Or better in English "while being in love ..."
E.g.: Он прожил всю жизнь, любя одну и ту же женщину. - He has lived all his life loving the same woman.

The negative form "не любя" is just "not being in love", "without being in love", "without loving":
Трудно жить, никого не любя. - It is hard to live without loving someone.