Wow, Orlander you have been through the same thing that I went through with my former bf or almost 8 years.
In January my ex told me that he loved me and wanted to marry me, but at the same time started a relationship with another girl online. When I found out about it we broke up, afterwards he met up with her and in less than 4 weeks they got engaged.
I didn't know the seriousness of the relationship as he claimed that she was just a "friend" (he lied) and I met up with him 2 days before and had sex with him (I know, bad), he was still upset over our break up and he cried to me about it and yet he got engaged to her 2 days later.
I was in so much shock and disbelief, but this did help me to start thinking that I really could not go back to him at that point, and I was stupid enough to beg him to come back to me.
I have not contacted him for 2 weeks now, and I don't even think that I can even look at him anymore because he slept with me when he was with her. I just feel like a total fool, I was with him for so long and yet I got no commitment from him and he knows this girl for less than 2 months and they are engaged...