Hurt and confused

My best friend of 12 years has been really distant from me since she got in her first serious relationship . She know has a one year old little boy I was there for his birth and then after that I have seen them maybe 2 or 3 times . It's bothered me for a while but I've just trier to make plans with her to go to lunch or take her son to the park anything just to spend time with them . I've always felt like she had an excuse that she was too busy and the I found out that she wasn't making her car payment for the car I consigned for on time and so I asked her what was going on and reminded her that I helped her out and that she needs to do her part by paying her bill and it caused this even bigger rift in our friendship . Now she texts me last night to tell me she loves me for all I've done for her but that she just feels like she makes me unhappy and that we have grown apart . Mind you this girl lived with me for 5 years when her dad died my family gave her a home and a family when she didn't have one and I just feel like no because she has a family of her own she dosent need me anymore and it hurts . Has this happened to anyone else ? Did I do something wrong I'm just so hurt and confused