I'm new to posting on this site although I've read quite a few posts on here in the past. Today, I decided I needed to vent and get some advice. I will try to be as brief as possible with my history. I am a childless (not by choice) 46 year old woman who has been dating a 40 year man for 2 years now and he has one child a 16 year daughter with a woman he never married but who he dated off and on in high school and several years afterwards trying to make it work. I have been married twice before with no children in the picture. My first marriage lasted only 3 years. I was young and married the wrong abusive guy so I divorced him. Second marriage ended after 11 years mutually we just grew apart. I never attempted to get pregnant during the first marriage but actively tried in my second marriage. Went through infertility treatments and considered adoption but ultimately my second ex-husband wasn't really on board for it so that was that and probably lead to part of our decision to divorce. I can honestly admit to the fact that I will never get over the fact that I will never have kids or ever be called mom. My boyfriend has never been married and hasn't really had that many long term relationships in the past. He has only ever introduced his daughter to one other ex-girlfriend besides me which I find very respectful since he said he never wanted to bring women around her if they had no intentions of becoming long term girlfriends. Fast forward to 2 years ago when we met. At first it was just casual dating and at the time I don't think either of us were looking for a relationship but after about 3 months we both knew it was turning into something more. He told me he had a teenage daughter and at first I wasn't sure about dating him as I have never dated any man with children before but since it was so new I decided to just let things go and see what happens. And as silly as it may have seemed at the time I thought well if things did work out this might be my last opportunity to have a child in my life and get a chance at being a mom sort of. The birth mom is the custodial parent and he use to get his daughter every weekend prior to her turning into a busy teenager. He didn't introduce me to his daughter until about the 3 month mark. She was reserved with me at first which I totally expected since I'm sure her Dad having a girlfriend wasn't something she was use to. We also lived in 2 different towns. He was living at home with his mother and I was living in my own home. After about a year I sold my home and started living in a rented condo. We still dated and I really only saw his daughter during her volleyball & softball games and other school functions or holidays. Overtime we have now built a good relationship. She is respectful, kind and helpful and never really gives her Dad or BM much trouble. About 9 months ago we decided to move in together and I purchased a new home. We have a bedroom for his daughter and I have made every attempt at creating an environment for her to feel welcome in. I have been to almost every single volleyball and softball games she has had since I was in the picture even one's where Dad couldn't make it I was there. I have been to choir concerts and other school functions. My boyfriend doesn't make a lot of money and is trying to catch up on back child support payments so most of his money goes towards her. However, there have been times where she needed clothes or shoes for volleyball or softball or money for a homecoming dress or shoes and I would pay for them. All without her knowledge of course. Her BM also picked out a used car for her 16th birthday and asked for her Dad to pay something towards it. He of course had no money so I volunteered to give $2,000 towards it again without anyone else's knowledge. I have purchased Valentine's day presents and Easter gifts and given her gas money anytime we see her all with her thinking its from her Dad. I don't expect acknowledgment from her. I do these things because I genuinely have come to love her and I know her Dad can't provide that much. I actually love when she does come to stay with us even though its only been several times. I can honestly say she is joy to be around. Lately my boyfriend has been talking more and more about getting married. Obviously, I am feeling very cautious since I've already had 2 failed marriages and would hate to make another mistake especially when there is a child involved. My main concern is the relationship I don't have with the birthmom. She is respectful to me whenever I see her at games and such but other than that she will have nothing to do with me. I don't expect to be friends with this woman but I would like to have a better relationship with her than it currently is. I feel isolated and like an outsider whenever I am around her or other family members. She is married and has another child with her husband and I know there is no chance of my boyfriend and her getting back together but I can't help but feel jealous of the bond that they share and the fact that I will never have that with him. She knows I can't have children and how much her daughter means to me and yet I still feel as though she will say things to make me feel like I'm an intruder and that I don't belong. My boyfriend and the bm have a decent relationship to the point where he will text her on the holidays and Happy birthday and Happy Mother's day and they talk on the phone every so often but actually I'm not sure how often because it is usually when I'm not around. I guess this is what has lead me here. I feel left out. One part of me is happy that they can co parent well for his daughter but on the other hand I'm jealous that he texts the bm about random day to day things or when I'm around they bring up the past and bm seems to purposely say things like "our daughter did this or your daughter did that" almost as if she knows what a hurtful stab that must be to me knowing she will always have that bond with my boyfriend and the fact that I don't have kids of my own. It also hurts when my boyfriend will make statements about his parenting issues saying that I wouldn't understand because I'm not a parent. I know my lane and I try to stay in it. I don't usually voice my opinion on parenting issues when he does discuss them with me which is rare. And I feel like I've been nothing but supportive of his daughter and their relationship even to the point when I have encouraged him to spend more time with her. Maybe its just me and my insecurities or maybe I'm being overly emotional. All I know is that what I thought was going to be a blessing lately has me feeling like a mistake and that maybe I shouldn't be with someone who has kids knowing I may not be able to handle it emotionally. Just wondering if this is normal or irrational.