You are not to blame for your father’s unfortunate and sad choice. A fight with a daughter is not enough for a person to end his own life. My guess is that he was dealing with a great many things and felt helpless to change them.
Often people like those in your family blame someone because it is just too, too hard to accept that they didn’t see it coming and they hadn’t helped. When a tragedy happens, people cast about for a way to make sense of it. They may not, in fact, have had any more to do with your dad’s suicide than you did, but they may be fending off feelings of responsibility and self-blame by blaming you.
I suggest you contact a women’s center. Often women’s centers have a resource and referral office that helps people connect with services they need. The center itself may have support groups running. Another avenue for support is the communities of faith in your area. It may be that one of the religious leaders is open to providing counseling for someone who can’t afford to pay for therapy. Sometimes hospitals offer grief groups too. When I did a web search for grief groups in your area, I found quite a few. Ask your doctor if she or he knows of any services as well.
I hope you find a group. The support of other people who know how you feel will give you some relief. Eventually, I hope the family gets some family therapy so they can stop making you the focus of their grief and you can feel comfortable in family gatherings.
I wish you well.