If she cares for you and always takes interest in your activities then she truly loves you.
The passion with which she looks at you gazing straight into your eyes, that means she is in love with you.
If you come to know from her family and friends that she often brags about you shows her love for you.
If a girl tries to get closer to you by touching your hands, shoulders or cheeks means she likes you.
When a girl blushes on your talks and keep praising you in front of your friends then she loves you.
If she is not afraid to hold hands with you in public.
A girl is deeply in love with a guy is she accepts his family no matter how they are.
If she always encourage and motivate you to go ahead with your plans then she is an ideal lover and is sincerely attached with what you want from your life.
If she wants to spend some time with you and want to help you out in every project or assignment means her love for you.
She calls you just because she was thinking about you, misses you, or just felt like it etc.
She wants to spend as much with you as is possible - clears up her busy schedule and makes plans just for you, travels long distances just to be with you etc.
She tells you she loves you and means it.
She does small unexpected things to pleasantly surprise you- sends an email message, shows up at your workplace, gets you something you always wanted etc.
She takes time to choose her gifts for you - regardless of the price tag.
She knows exactly what makes you smile, feel special and taken care of.
She shows interest in your life - asks about your day, family, friends and work; remembers whatever say and do etc.
She wants a future with you in it - talks about it and plans for it.
She talks to you about things he/she doesn't talk about with anybody else.
You just know it - no doubting, no questioning, no wondering, no convincing or trying to make her love you and no strings attached. You look into her eyes and you know it. Something inside of you just knows.
If you really want to know just ask her about her feelings for you.