Discovered a Lady's Pant in His Bathroom!

Good morning  Aunty Amara, am a 24 years old girl, I met this guy a 30 old man at my bestie's wedding this year January 2nd, he is the cousin to my bestie hubby,we got talking and started dating but before we started my friend(infact she is like a sister) and her hubby( his cousin) met him and asked him that if he was not serious with me he should not go close because of my past experience, he assured them and told them his intention was marriage. 
When we started it was a dream relationship I was always around him, his friends were so fond of me, he was my dream come true till this year August when I went to his house and discovered a lady's pant in his bathroom. 
He pleaded and after much talk from my friend I forgave him. He got a new car and after that he totally changed, different girls started calling him in my presence and when I asked him, he will say that they were just friends, this continued till when I was forced to check his phone and saw he was dating them and when these girls asked about me, he denied not knowing me.
I confronted him and he got angry saying I was the cause of it, I started seeing different things and signs like him switching off his phone when he is back from work, he stopped chatting me, he doesn't ask me to come visit him. 
Then one day I came to his place and was sleeping his house, I saw used condoms in his dustbin, I asked him and he admitted of bringing a girl to his house that I was the cause, I became angry and we started having problem and it seemed it over now, everyone was very disappointed in him but he doesn't care, in the cause of his financial problem he borrowed money from me and now he has refused to pay me back. 
Aunty Amara I love him sincerely, it's so hard for me but I need to get myself? 
Please what do I do am so down......

The moment there was a pant in the picture ought to be the best time to wave goodbye to him. 
Not that he couldn't have repented but most times, the girl whose pant hangs in a man's room is the one who controls his heart...lol 
I understand that you love him but the truth is that he never took you seriously because he simply caught you with the help of your friend and her husband. 
It was as though they gave him the password to mess up with your life and emotions hence his nonchallant attitude towards you and the relationship. 
That you even had to sleep in his room and dispose his condom only points to one thing that he's a chronic cheat and a hopeless womaniser which makes me wonder what exactly you love in him when you can possibly contract tons of infections and diseases from him in a word go. 
Forgive yourself for being sentimental about everything concerning him, maybe you should read my article on When you should snap out of a terrible relationship and learn to manage your emotions and your thoughts when you need to make some critical relationship. 
That you are in love with a man doesn't mean that you should reduce yourself to a door mat for all sorts and kinds of abuse and embarrassments. 
No need for the confrontations and painful conversations with him, it's obvious and sincerely pathetic for you to hang around with him for whatever promises you cannot guarantee. 
God is faithful even when we are disappointed by men and his promises would never change because of our experiences. 
This is the best time to reconnect to God and simply allow him to guide your steps and strengthen your heart. 
Because he has done it for many, yours wouldn't be an exception, please cheer up and look up, there's help from above.